初二下总复习1-10单元复习题

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八年级下学期各期末总复习各章单元测试试题 (7套)

金牌教育一对一个性化辅导教案八年级（下）数学期末总复习题一（不等式和不等式组）一、选择题(2分³15＝30分)1、如果a ＞b,那么下列不等式中不成立的是……………………………………………( ) A ． a ―3＞b ―3 B ． ―3a ＞―3b C ．3a ＞3bD ． ―a ＜―b 2、不等式组⎩⎨⎧>+≤0312x x 的解集在数轴上可表示为…………………………（）3、已知两个不等式的解集在数轴上如图表示，那么这个解集为（） A 、x ≥－1 B 、x >1 C 、－3<x ≤－1 D 、x >－34、使不等式4X+3＜X+6成立的最大整数解是…………………………………………( ) A ． ―1 Ｂ．０Ｃ．1 Ｄ．以上都不对5、若不等式（ａ―５）ｘ＜１的解集是ｘ＞51-a ，则ａ的取值范围是………（）Ａ．ａ＞５Ｂ．ａ＜５Ｃ．ａ≠５Ｄ．以上都不对 6、已知一次函数y=-65x-310,当y<0时，x 的取值范围是A 、x>4B 、x<4C 、x>-4D 、x<-47、如果a<b<0，那么不等式ax<b 的解是……………………………………（）10、不等式组⎪⎩⎪⎨⎧<+->->-0202052x x x 的解集是………………………………………………（）A 、225-<>x x 或B 、225<>x x 或 C 、25>x D 、无解12．下列说法①0=x 是012<-x 的解 ②31=x 不是013>-x 的解 ③012<+-x 的解集是2>x ；④⎩⎨⎧>>21x x 的解集是1>x ，其中正确的个数是（） A ．1个B ．2个C ．3个D ．4个14小明用30元钱买笔记本和练习本共30本，已知每个笔记本4元，每个练习本4角，那么他最多能买笔记本（）本 A ．7 B ．6 C ．5 D ．4 15、不等式组⎩⎨⎧>-<+-mx x x 62的解集是4>x ，那么m 的取值范围是（）A ．4≥mB ．4≤mC ．4<mD ．4=m 二．填空题(3分³5=15分)16、用“＞”或“＜”填空，并写上理由。

八年级英语下册模块1-10单元复习题

八年级下册模块1-10单元复习题Unit 1一翻译下面的短语和句子.1 一百年以后___________2 喜欢上______________3 去滑冰____________4 在周末____________5 能,会______________6 实现____________7 在未来___________ 8成百上千的____________9 尽力做_____________10 使得某人做__________ 11 醒来_________ 12 一次又一次____________13 太空站__________ 14 人们将会活到200岁.___________________________15 将会有更少的污染吗? 不,不会.______________________ _______________16 五年前她踢足球.________________________7 我不喜欢独自居住_____________________________.18 预测未来可能很困难._________________________.19 有一天人们将飞往月球度假._________________________________________.20未来的学生将在家通过电脑学习._____________________________________.二用more, fewer, less, little, few填空.1 He has ______ books than I have.2 There is _____ snow this year, and the earth is very dry.3. He is very busy. He has _____ free time.4 There is _____ food left at home. Let’s go and buy some.5 There are ______ apples on the table. You can eat some.6 There will be ______ pollution if we don’t do something to stop it.7 We can do the work with ____ money and ____people than they can.三用所给词的适当形式填空.1 His father _______ ( not be) back home in a week.2 Li Ping always _____(reach) school early. 3 He will go ______ (swim) next Sunday. 4 Are you enjoy _____ (live) here? 5 Now he ____ (be) a student. Three years ago he ______ (be) a pupil. Next term he ______ (be) in high school. 6 There ____(be) a class meeting next Friday and our teacher ______ (have) something to say. 7 No one will want ____ (see) actors ____ (talk).8 He thought computers would never ______ (use) by most people. 8 We are able ____(have) our own robots. 9 Would you like _____ (do) such job?Unit 2一翻译下面的短语和句子.1 和…争吵__________2 过时的____________3 给…打电话___________4 球赛的票___________5 令…吃惊的是___________6 谈论____________7 付钱,赔偿__________ 8 向…借___________ 9 兼职工作______________10 时髦的___________ 11 和…相同_________ 12 发现,查明____________13 祝你好运__________ 14 生…的气_________ 15 年龄相同____________16 相处得好__________ 17 和…吵架____________18 抱怨_____________19 到了…的时间__________________________ 20 参加_______________21 各种各样____________ 22 一方面__________23 另一方面_____________24 你应该给他写封信._______________________ 25 这儿除了你我不认识任何人_______________________ 26 你和你父母相处的怎样?______________________27 他和我有相同的发型.___________________28 我不想在电话上谈此事_______________________ 29 她很烦恼,不知该怎么做.___________________________ 30 你能给我一些建议吗?_____________________ 31 星期三,他把书落在家里了. ___________________32 我妈妈在为我准备一次生日聚会.__________________. 二用所给词的适当形式填空.1 If you want better grades, you ______(should) watch so much TV.2 I find it difficult ______ (get) to sleep in the night. You’d better ____-(take) some sleeping pills. 3 My parents want me _____ (stay) at home.4 The teacher told me ______ ( not be) late again.5 I’m sorry I didn’tfinish _____ (write) my homework. 6 I’d like you ____ (play) with us.三句型转换1 He has some money, too.(否定句) ___________________2 It seems that Kate has supper at home.(同义句,下同)_______________3 He is so strong that he can carry the heavy box.__________________4 I don’t know what I should write to h im._______________________5 What’s wrong with it? _________________6 The picture cost me ten dollars.________________7 Joe gave me a call just now. ____________8 Emma wears a red jacket. So does her sister.________________________Unit 3一翻译下面的短语和句子.1 在…前面__________2 睡懒觉___________3 到达______________4 从…出来__________5 报警_____________6 沿着…走_____________7 起飞______________8 对…吃惊___________ 9 跳下_____________10 拍照_____________ 11 在火车站___________ 12 逃跑_____________13 考虑_____________ 14 紧挨,靠近___________15 寻找_____________16 听说___________ 17 在…城______________ 18 在那时_____________19 沉默地___________ 20 发生____________21 在太空中______________22 全世界_____________23 在医生诊所______________24飞碟到达时你在做什么? __________________________________________25 当老师进来时,学生们正在唱歌. ____________________________________26 昨晚8点我爸在看报. _______________________________________二用所给词的适当形式填空.1 My sister _____ still _____ (watch) TV when I _____ (go) to bed lastnight. 2 Mother ______ (clean) the room when I ____ (leave) home.3 Julia _______ (cook) when the doorbell ______ (ring).4 Grandma_______(cook) breakfast while I _______(wash) my face this morning.5 I _____(read) a history book when someone ____ (knock)at the door.6 She spent a _____ (quietly) evening reading at home.7 I found a dog ____(lie) on the ground on my way home. 8 Don’t make any ______ (noise). Thebaby is sleeping. 9 Lucy did everything much _______ (bad) than Lily.10 A _____ (clean) is a person who sweeps roads every day.三用when, while 填空1 _______ we were talking in the classroom, the teacher came in.2 _______ they got to the airport, it was raining.3 ______ she was reading a book, the phone rang.4 ______ I saw the boy, he was wearing a new coat.5 ________ he was reading, he fell asleep.Unit 4一翻译下面的短语和句子1 举行一个惊喜聚会___________2 不再__________3 首先_____________.4 在星期五晚上______________5 传递___________6 被期望____________7 擅长____________ 8 在…干得更好____________ 9 身体健康______________ 10 年终考试____________11 成绩单__________ 12 抄…的作业___________ 13 在…有困难__________ 14 大吵一架___________ 15 忘记去做__________ 16 养成坏习惯__________ 17 生…的气___________ 18 克服_____________19 海拔2000米__________ 20 两者都___________ 21 每天三次___________ 22 在两者之间____________ 23 高中_____________ 24 打开_____________25当数学老师_____________ 26 照顾__________ 27 中国少先队____________ 28上周听说他感冒了我很难过. ___________________________________________29 她说她不想再做我最好的朋友. _________________________________________30 起初稀薄的空气让他不舒服. ____________________________________________ 二用所给词的适当形式填空.1 Listen! The children _________ (sing) in the classroom.2 _____ you_______ (read) when he knocked at the door?3 He told us _______ (not swim) in the river.4 He said he _______ (borrow) me the pen the day after tomorrow.5 I have no idea if he _______ (come) in five days.6 Remember _____ (bring) the book to school tomorrow.7 He is supposed _______ a kind man.8 Do you think _________ (there be) an English film tomorrow night?三把下列句子改成间接引语1 “What are you doing, Tom?”I asked Tom ________________________2 “Do you often come to school by bus?” He wanted to know ____________3 “Why can you finish it so soon, children?” Mom asked the children _____4 “Li Lin is better at English than math,” said the teacher.The teacher said that ______________________________5 “My father has been to Hong Kong twice.” He said ______________Unit 5一翻译下面的短语和句子1 为考试而学习___________2 拿走,带走__________3 拜访敬老院__________4 谋生___________5 一直,始终_____________6 到处跟着你_______________7 受伤___________8 让…进入__________-9 玩得高兴________________10 坐公共汽车__________ 11 学校聚会规定_________ 12 在聚会期间________ 二选择填空1 If you are late for school, the teacher ___ angry. A is B was C will be2 I met a friend of mine ___ .A on my way home B on my way to home3 They didn’t go to bed__they finished their homework. A until B when4 ___ kind girl she is! A How B What C How a D What a5 We shouldn’t _____ their mistakes. A to laugh B laugh at C to laugh at6 Thank you for ____ me the news. A tell B telling C tells7 It’s t ime for class. Please stop _____ A talk B talking C to talk8 My watch isn’t here. Maybe ____ took it. A somebody B anybody9 I don’t know if it ___ tomorrow. If it ___, we will stay at home.A rains, rainsB will rain, rainsC will rain, will rain10 You will have fun if you ______ tomorrow. A go hiking B will go hiking三用所给词的适当形式填空.1 I’m afraid I _____ (get) a cold tomorrow.2 Jim _____ (watch) TV at this time yesterday.3 There ______ (be) a film tomorrow evening.4 They ______ (work) here last year.5 We _____ (visit) your factory next week.6 Look! The children _______ (swim) in the river.7 She says she ______ (help) me with my English next year.8 What time ___she ___ (leave) home every day?9 We hear he____(return) next month.Unit 6一翻译下面的短语和句子1 一双滑冰鞋___________2 为慈善会筹钱____________3 多久___________4 整整五小时___________5 三年半_____________6 用完______________7 在我七岁生日时_________ 8 顺便问一句_________ 9 任何其他人_________10 对…感兴趣____________11告诉…关于… __________12 多于,超过________13 远离__________ 14 欧洲影响_____________ 15 丰富多彩的历史________16 有俄罗斯风格__________ 17 黑龙江省省会_______________18 我的爱好是收集旧硬币. _____________________________ 19 感谢你送我雪球._________________________ 20 我滑冰滑了五小时_________________________.二用for,since填空1 He has been practicing the piano _____ 9:30.2 Maria has been running ____ 15 minutes.3 Sarah has been sleeping ____ since 9:00.4 She has been studying ____ she was six years old.5 I’ve been watching you ____ ten minutes.三句型转换1 She has been working for 20 hours.(一般疑问句,否定回答) _____ she _____ working for 20 hours? No, _____ ______ .2 I’ve been skating since I was six years old.(提问)_____ _____ _____ you been skating?3 Tom ran for one hour.(用现在完成时改写) Tom ___ ___ ____ for one hour.4 We have been learning English for three years.(同义句) We have been learning English ____ ____ ____ ____.5 They have been to the West Lake twice.(提问) ____ ____ ____ have they been to the West Lake?翻译: 1你观看英语电影多长时间了?_____________________________2 他总是第一个到校的学生. ___________________________________3 考试中我没写完作文是因为我用完了时间.______________________Unit 7一翻译下面的短语和句子1 关小,调低___________2 立刻,马上____________3 过一会_____________4 洗餐具_____________5 起床__________6 去看电影_______________7 做晚饭____________ 8 没问题___________ 9 排队______________10 商店售货员___________ 11 到处跟着我__________ 12 插队___________13 尽力不做… ___________ 14 点菜____________ 15 压低声音____________16 即使__________ 17 小心,当心____________ 18 在公共场合____________19 破坏规定____________ 20 熄灭___________ 21 扔垃圾______________22 捡起,拾起____________ 23 允许做… ___________ 24 离…近___________25 你介意把音乐关小吗?一点也不.____________________________ ___________26 这只钢笔不能用了,你可以再给我看一只吗?_______________________________27 我在学校图书馆总有这样的事发生. ______________________________________28 你别穿这件衬衣好吗? __________________________29 对不起,我马上做.___________________30 当有人插队时我很生气.__________________________二选择填空1 Could you please ___ the radio, the news will start. A turn on B turning on C to turn on2 Can I ____ your car later? A make B to use C use3 Talking loudly in public is ___. A polite B impolite C politely4 Would you mind ____dumplings? I hate them! A not make B not making C making5 Could you tell me how to ___ it in English? A say B speak C tell D talk6 The teacher told the students _____ in class. A not talk B not to talk C not talking7 ____ must I take this medicine every day? Three times a day. A How long B How oftenC How soon 8 Everyone except Tom ____ there when the meeting began. A are B is C was 9 May I ____ your dictionary? Sorry, I ___it at home. A borrow, forgot B borrow, left C lend, left 10 Could you please _____ ? Oh, sorry. I will. A wait in line B cut in lineC wait in a lineUnit 8一翻译下面的短语和句子1 给…买… _________2 不够特别____________3 听起来不错____________4容易照顾____________ 5 太…而不能___________6 目前,现在____________7 给…制作… __________ 8 一点也不____________ 9 入睡,睡着_____________10 中途,一半___________ 11 太多_____________ 12 不同种类______________13 让她高兴____________ 14 赠送,捐献____________15 付钱,赔偿__________16 而不是___________ 17 代替,而不是____________ 18提高英语____________19 全中国__________ 18 和…一样… _____________ 19 各年龄段___________20 鼓励…做__________ 21 取得进步__________22 学英语获得乐趣__________23 查出__________ 24 听说___________ 25 对…感兴趣________________26 和…交朋友_____________ 27 以不同方式____________28 为什么不送她一条围巾? _________________________________ 29 那不够有创意._______________30送一本相册怎么样? ____________________31 他曾经收到的最好的礼物是什么?____________________________32 多么幸运的人! ___________________33 有时我没有足够的时间陪他一起度过.____________________________________34 在不同国家礼物的赠送是不相同的.______________________________________35 人们不必花太多钱,相反,做顿饭就够了.___________________________________36 有乐趣地学英语对他们来说是个好主意.__________________________________二用所给词的适当形式填空.1 Do you think your school life is _______ (color)?2 I’m afraid he hasmade the wrong _______ (decide) on that matter. 3 He got the gift on his _____(twenty) birthday. 4 They finished the job all by _____(them).5 You’d better ____ (stay) in bed until tomorrow.6 The box is too heavy for me ____(carry).7 Jack _____(return) from London in a week.8 Tom ______ (make) some progress in his lessons since last term.9 Look! They ______ (pick) apples from the trees now. 10 Would you like something _____ (drink)? 11 His brother _____(play) football at this time yesterday. 12 Must we _____(start) the work at once?13 His work ____ (finish) at half past five. 14 What time ____ Mr Read ____ (have) lunch every day?15 I want to go to the city ____ (call) shanghai.Unit 9一翻译下面的短语和句子1 曾经去过__________2 去了… _____________3 娱乐公园_______________4 太空博物馆___________5 坐地铁____________6 玩得高兴_____________7 过山车_____________ 8 兜风_______________ 9 在船上_______________10 走不同路线_____________ 11 以..结束___________ 12 和…争吵_________13 空姐_______________ 14 导游____________ 15 例如______________16 上课_____________ 17 度假______________ 18 四分之三_____________19做…有问题___________ 20 醒来____________ 21 在白天______________22 睡着的_____________ 23 一年到头___________24 离…近_____________25 远离___________ 26 无论何时______________ 27 在夜晚_______________28 你曾经帮助过你不认识的人吗? ________________________________________29 你曾经去过说英语的国家吗? ___________________________________________30 我需要提高我的听力技巧.____________________________________________31 我毕业后,将做英语老师而不是导游. _____________________________________32 他从未去过水上世界,我也没有.__________________________________________二用所给词的适当形式填空.1 Have you____ (see) my pen ? I ___(put) it on the shelf a moment ago.2 --John, _____ you ____ (return) my pen yet? –Not yet. I ____ (return) it soon.3 –Jim, ____ you ____ (write) a letter to your aunt? Yes, I ____-- When ____ you ____ (write) it ? –I _____ (write) it last week. 4 I’llthink about _____ (become) a tour guide. 5 It’s fun ____ (learn) another language. 6 When did you start _____(study) English? 7 _____you ____ (see) the film before? Yes, I _____(see) it last Friday.三选择填空1 Neither of the books ___ written by the writer. A is B are C has2 Neither you nor he ___ worried. A are B is C am D has3 Her grandmother ___ in 1985. She has been ___ for 22years. A died, died B dead, dead C dying, death D died, dead 4 I have never been to European countries. What about you ? ______ A So have I. B Neither have I C Neither do IUnit 10一翻译下面的短语和句子1 看起来象____________2 到中午___________3 在周末_______________4 浏览_______________5 有点热_____________6 因…而感谢____________7 喜欢,想要___________ 8 过来______________ 9 在…帮助… _____________10 进展,相处___________11 考虑,想到___________ 12 过马路_____________13 对…友好___________14 告诉…关于… ___________ 15 他肯定是. __________16 天看起来要下雨了. _________________ 17 我希望如此. ________________二把下列句子变成反意疑问句.1 You are Bill’s friend, _________?2 They’re always friendly, ______?3 He isn’t good at math, ________?4 You go to school by bus, _____?5 She has never been there, ______ ?6 They can’t swim, _________?7 There’s little milk in the glass, ______? 8 He won’t be back, ______?9 They went to the USA, _______ ? 10 Jim must stay at home, _____?11 Tina has been learning English for three years, _________ ?12 Li Lei has more than 100 stamps, __________ ?13 Let’s clean our classroom, _________ ? 14 W ait a minute, _______?三句型转换1 Have they traveled on a train? (否定回答) ________________2 They were so tired that they couldn’t walk any longer. (同义句)They were ______ tired _____ walk any longer.3 All of us want him to rest.(否定句) _________________________4 They spent 10 years building the bridge.(同义句) It ____ them ten years to_______ the bridge. 5 She can’t speak English or French. (同义句)She can speak ______ English ______ French. 6 She has to clean the roomtwice a day.(提问) _____ ______ does she have to clean the room?。

八年级下学期期末复习讲义(总) 1-10 单元

【单词部分】1.stomach 胃复数：stomachs stomachache 胃痛headache 头痛2.foot 脚复数：feet neck 脖子throat 喉咙3.lie down 躺下take one’s temperature 量体温4.break 休息take a break /take breaks5.hurt doing sth 做某事受伤6.passenger 乘客复数：passengers7.to one’s surprise 使某人惊讶8.right away 立刻get into 加入9.反身代词：herself ourselves itself10.c limber 登山者rock 岩石11.t ake risks 冒险get out to 离开12.k ilo 千克复数：kilos13.k nife 刀复数：knives cut off 切除14.b lood 血液bleed 流血15.I mportant 重要的importance 重要性16.m ake a decision to do sth 做决定去做某事17.b e in control of 掌管；管理18.S pirit 勇气；意志the Spirit of19.d ie 死过去式：dead 名词：death 形容词：dead【课文部分】1.drink some hot tea with honey 喝一些带有蜂蜜的热茶2.see a dentist 看牙医get an X-ray 拍X光3.put...on 把...放在...上4.Shout for help 大声呼救5.expect sb to do sth 期待某人做某事6.agree with sb agree to do sth7.thanks for 谢谢thanks to 多亏了8.be saved by doctors 被医生救9.lose one’s life 失去某人的生命10.t ooth 牙齿复数：teeth【单词部分】1.clean up 打扫make a difference 影响2.cheer up 振奋起来give out 分发3.volunteer to do sth 志愿做某事volunteer...as...志愿做e up with 提出5.hand out 分发call up 打电话；号召ed to do sth 过去常常做某事be used to doing sth 习惯于做某事7.Several 一些a couple of 一些8.feeling 感觉复数：feelings wheel 车轮复数:wheels9.satisfaction 满足；满意10.o wner 主人raise 募集repair 修理fix 修理11.g ive away 赠送take after (外貌或行为）像12.t ry out 参加...的选拔set up 建立13.d isabled 有残疾的blind 瞎的deaf 聋的clever 聪明的14.I magine 想象difficulty困难15.人：excited 物：exciting 名词：excitement16.K indness 仁慈interest 兴趣change 变化journey 旅行17.n otice 通知可数名词notices【课文部分】1.give up doing sth 放弃做某事2.强烈的满足感：a strong feeling of satisfaction3.Volunteering here is a dream come true for me.4.decide to do 决定做某事help do/to do sth 帮助做某事5.be worried about 对...担忧6.run out of 用光7.be similar to 和...一样8.make it possible for sb to do sth 使做某事成为可能9.极好的：fantastic wonderful pretty10.a sk sb to do sth 要求某人做某事11.告诉某人做某事：tell sb to do sth 告诉某人不做某事tell sb not to do sth12.u sed to be 曾经是13.a t the same time 同时14.a trained dog 一只被训练的狗15.h ope to do sth 希望做某事没有hope sb to do 的用法16.b ecause 因为,后面接句子;because of 由于，后面接短语17.Y ou needn’t go to his house. need 在此为情态动词，所以后面为原型18.b asketball lover 篮球爱好者Unit 3【单词部分】1.rubbish 垃圾take out the rubbish 倒垃圾2.Sweep 打扫过去式：swept sweep the floor 扫地3.threw 扔过去式：throw 短语：threw down drop 下落4.all the time 频繁5.both 两者都neither 两者都不either 两者中的任何一个6.as soon as 一...就...7.borrow 借borrow sth from sb 从某人处借；lend 借给lend sth to sb 借给某人8.finger 手指fingers9.hate doing/to do sth 讨厌做某事10.do chores 做家务in order to 为了11.a waste of 一种...的浪费waste time doing sth 浪费时间做某事12.provide sb with sth/ provide sth for sb 提供（注意区分接人还是接物）13.anyway 而且depend on 依靠develop 发展development 发展14.Independence 独立fairness 公正性fair 公平的unfair 不公平的15.neighbor 邻居neighborhood 社区16.take care of =care for=look after 照顾17.ill 生病的illness 疾病【课文部分】1.help out with sth 帮助做某事2.be enough to do sth 做某事足够3.clean and tidy 干净整洁的e home from school 从学校回到家5.Invite sb to do sth 邀请某人做某事6.make sb do sth 让某人做（原型）7.There is no need for sb to do sth 对于某人所说做某事不需要8.It’s +形容词+for sb +to do sth 形式主语9.pass sb the salt 把盐递给某人fold the clothes 叠衣服make the bed 铺床10.I n surprise 吃惊地take the dog for a walk 遛狗11.a s ...as... 和...一样... as tired as me 和我一样累12.短语中，代词放中间例：take them out, give it away13.在计算机上工作work on computer14.S ince 不但要自从的意思，还有因为的意思15.T he earlier,the better 越早越好16.培养独立的能力develop our independenceUnit 4【单词部分】1.allow sb to do sth 允许某人做某事2.look through 浏览a deal 交易big deal 重要的事3.work out 解决cut out 删除get on with/get along with 和睦相处municate 交流communication relation between... ...的关系5.argue with 与某人争吵compete with 与某人竞争competition 竞争6.elder 年长的older old 的比较级7.nervous 紧张的proper 合理的typical 典型的crazy 疯狂的8.offer to do sth 自愿做某事push 推动development 发展9.first secondly third forth twelfth twentieth10.c lear clearly 清晰地quick quickly 快地usual 寻常的unusual 不寻常的11.n ot ...anymore 再也不real 真的really12.m ember 成员复数：members13.p ressure 压力stress 压力a lot of pressure 大量的压力14.o pinion 观点in one’s opinion 依某人看15.c ompare ...with 与某人比较perhaps 大概【课文部分】1.Why don’t you talk to your parents?=Why not talk to your parents?为什么不和你的父母谈一谈？2.enough 足够的搭配形容词：busy enough 搭配名词：enough food3.free time 闲暇时间hang out with 与某人闲逛4.too many +可数名词复数too much+不可数名词5.get into a fight with 和某人打架be angry with sb 对某人生气6.call him up 给某人打电话talk about 谈论7.give sth back to sb 把某物给某人write a letter to sb 给某人写信8.think for oneself 独立思考9.be nice to =be friendly to 对某人友好refuse to do sth 拒绝做某事10.a lone 单独；独自例：live alone 独自生活lonely 孤独的feel lonely11.m ind sb doing sth 介意某人做某事of course not 当然不12.害怕做某事be afraid to do sth /of doing sth13.g et into a high school 进入高中14.I t’s time for homework =It’s time to do homework 到了做作业时间了15.e xplain 解释explain to sb 向某人解释16.建议：advice 不可数some advice 动词：advise suggestion 可数suggestions17.f riendly 比较级：friendlier18.I disagree with you 我不同意你19.U ntil 直到unless 除非20.W ithout doing sth21.t rain 火车training 训练22.W hat’s the matter with you?What’s wrong with you?你怎么了？Unit 5【单词部分】1.go off （闹钟）发出声响2.heavy 重的heavily adv. 在很大程度上3.Suddenly 突然strange 奇怪的4.match 火柴复数：matches beat against 击打5.asleep 睡着的awake 醒着的fall asleep 进入梦乡6.die down 逐渐变弱dying down rise 上升rising7.fallen 倒下的broken 坏了的icy 结冰的8.make one’s way to sw.前往某地plete 直接+ly completely 彻底地10.I n silence 在沉默中recently 最近11.t ake down 拆除truth 实情tower 塔date 日期【课文部分】1.本单元所学为过去进行时，was/were + doing sth 过去某时刻正在做某事2.What were you doing last night？I was doing my homework.3.While 后面接延续时态was/were doing sthWhen 后面可以延续，也可以不延续（可以是一般时态，也可以是进行时态）4.pick up 接听电话Point out 指出go away 离开5.at that time 在那时at the time of the storm 在暴风雨之际6.make the sky dark 使天空变黑fell like 像...一样7.In a mass 脏乱不堪in times of difficulty 在困难时期8.take 带走bring 带来right away 马上9.the side of road 路边wait for sb to do sth 等待某人去做某事10.r emember to do sth 记得去做某事remember doing sth 记得做过某事11.I n history 在历史上an important event 重要的事件12.b e shocked to do sth 做某事很震惊has meaning to 有意义13.I was so scared that I could hardly think clearly.14.H ave trouble/problem (in) doing sth15.发生在某人身上：happen to sb in the face of 面对16.Y ou are kidding 你在开玩笑17.回家walk home （不是walk to home）18.t ake off 起飞put off doing sth 推迟做某事Unit 6【单词部分】1.shoot 射击shoot at sth 瞄准，强调动作shoot sth 射中，强调结果过去：shot2.Remind remind sb of sth 使某人想起某事remind to do sth 提醒某人做某事3.instead of 代替turn ...into... 变成4.Once upon a time 从前fall in love with sb 爱上某人5.Smile 变ing 去e 加ing smiling6.Get married to sb 与某人结婚7.Silk 丝绸stupid 愚蠢的silly 愚蠢的cheat 欺骗8.a little bit 有点儿，稍微=a bit9.excite 人：excited 物：exciting 名词：excitement A couple of 几个10.n obody 作主语时后面跟第三人称单数11.w hole 整个形容词12.s hine 发光过去式：shone 现在分词：shining【课文部分】1.Journey to the West 西游记Yu Gong Moves a Mountain 愚公移山2.Hou Yi shoots the Suns 后羿射日Nv Wa Repairs the Sky 女娲补天3.Be working on doing sth 从事做某事as soon as 一...就...4.Continue to do sth 继续做某事moved adj. 感动的5.take away 搬走come out 出版；发行6.This story reminds us that you can never know what’s possible unless you try to make it happen.这个故事告诉我们除非你去努力使他发生，否则你永远不会知道可能会是什么样子。

人教版八年级英语下册第1-10单元练习题及答案

八年级英语下册第1-10单元练习题及答案一、单项选择：20分( )1. I ___ think there ____ more pollution.A. /, won’t beB. don’t, will beC. /, won’t haveD. don’t, have( )2. I’m going to be a doctor ____ five years. A. after B. during C. in D. for ( )3. You always say ____ words as our teacher. A. so B. as C. the D. the same ( )4. She has ____ to buy a car.A. money enoughB. many moneyC. enough moneyD. a few money ( )5. Is there ____ in the classroom now?A. someone elseB. else someoneC. anyone elseD. else anyone ( )6. ___the boy was walking down the street, the UFO landed.A. WhileB. WhenC. WhatD. Where( )7. This book is very ___ and I am ____ in it.A. interest, interestB. interesting, interestedC. interested, interestingD. interested, interested( )8. –Could you please tell me ____? -It’s next to the post office.A. where is the supermarketB. where the supermarket isC. where was the supermarketD. where the supermarket was( )9. I want to know if he _____ tomorrow. I f he _____, let me know.A. come, comesB. will come, comesC. comes, will comeD. will come, will come( )10. T om asked me _____ him a book. A. give B. to give C. giving D. gave ( )11. –How long has the weather been like this? - ______.A. Until last nightB. Since last nightC. Two days agoD. Two days later( )12. The boy always stays there for ____.A. one and half hourB. one and a halfC. one and a half hourD. one and a half hours( )13. It’s too hot. Would you mind ____ the door?A. to open B. opening C. opens D. opened ( )14. He often helps me ____ my English. A. on B. with C. at D. in( )15. The young man is _____ to carry the heavy stone.A. enoughB. too strongC. so strongD. strong enough( )16. - ____do you ____ the movie? - Very good.A. What, thinkB. What, likeC. What, think ofD. How, think of( )17. Have you ever ____ Fun Time Amusement Park?A. gone toB. been toC. beenD. went( )18. Jim likes playing ____ piano after school. A. a B. the C. / D. on( )19. He’d like ____ a famous singer. A. be B. being C. to be D. been( )20. There is _____ water left, is there? A. a little B. little C. a few D. few二、完型填空：10分There is good news for the children in the countryside. We may still remember the girl 21 big eyes. Her big eyes are 22 us her dream: I wish to 23 ! In China, there are still 24 girls and boys like her. They want to go to school, but their 25 are too poor. If the family has two or three children, it is harder to 26 the money for all the children. So the parents often ask 27 to stay at home, and boys to go to school.Now they needn’t 28 the money. From 2006 on, children can go to school for free in some poor places. They don’t have to pay for books and other things. Some of them can even getmoney from the government to make their life 29 . Soon, all the children in the countryside can go to school for free. All families are very happy with the news. It is 30 great.( )21. A. with B. on C. to D. in( )22. A. saying B. telling C. speaking D. talking( )23. A. go to work B. go to bed C. go to school D. go home( )24. A. a lot B. lo t of C. a lot of D. much( )25. A. schools B. cities C. houses D. families( )26. A. pay B. take C. buy D. lend( )27. A. teachers B. girls C. boys D. all the children( )28. A. look up B. turn on C. worry about D. make sure( )29. better B. shorter C. longer D. worse( )30. A. not B. never C. hardly D. really三、阅读理解：40分A.One day an Australian farmer, Joe, saw a bright light in the sky. The light came nearer and nearer and suddenly Joe saw that it was a spaceship. The spaceship landed in a field nearby.The door of the spaceship opened and two strange beings(怪物) climbed out. They seemed to be half man and half bird. Joe was afraid of them. He tried to run away. But the spacemen walked towards him, picked him up and carried him into the spaceship.They asked him questions about Earth. “We’re from Venus(金星)，”they said, “but it is getting very hot there. A lot of our people are dying and we haven’ t much time left. We are trying to find a new home.”After some time they freed Joe and at last the space-ship took off and could not be seen.Joe told his friends about the spacemen, but no one believed(相信) his story.“You will believe me one day”, Joe told them. “The spacemen will come back...”( ) 31.The bright light in the sky was______.A. the sunB. VenusC. a machineD. a spaceship( ) 32.The strange beings came to Earth to______.A. visit JoeB. catch JoeC. find a new homeD. live with Joe( ) 33.Joe was ______the spaceship.A. invited toB. afraid ofC. carried intoD. happy to get into( )34.The strange beings ______before they let him go.A. had asked Joe to mend their machineB. had asked Joe several questionsC. had given Joe some wiresD. had made Joe help them find a new place( )35.People didn’ t believe Joe because______.A. he told a lieB. it hadn’ t been seen beforeC. they didn’ t welcome the strange beingsD. they wanted to see the strange beings very muchB.Hundreds of years ago, life was much harder than it is today. People didn’t have modern machines. Life today has brought new problems. One of the biggest is pollution. Water pollution has made our rivers and lakes dirty. It kills our fish and pollutes our drinking water, noise pollution makes us talk louder and become angry more easily. Air pollution is the most serious kind of pollution. It’s bad to all living things in the world.Polluted air from cars, planes and factories is to thick that it is like a quilt(被子)over a city. This kind of quilt is called smog(烟雾). Many countries are making rules to fight pollution. Factoriesmust now clean their water before it is thrown away. And they mus tn’t blow dirty smoke into the air. We need to do many other things. We can put waste things in the dustbin and not throw it on the ground. We can go to work by bus or with our friends in the same car, if there are fewer people driving, there will be less pollution.Rules are not enough, every person must help to fight pollution.( )36. Hundreds of years ago, life was much harder than it is today because _____.A. there were fewer modern machines at that time than today.B. people didn’t like to use modern medicines.C. there were no modern machines at all.D. there were not so many people( )37. What is the biggest problem in today’s life?A. Dirty water. B. Smog. C. Noise. D. Pollution. ( )38. The most serious kind of pollution is ______.A. noise pollutionB. air pollutionC. water pollutionD. from waste things ( )39. Factories must clean their water ______.A. before they use itB. when they use itC. after it is thrown awayD. before it is thrown away ( )40. From the passage we know that ____.A. a few years ago, there was no smog at allB. today people don’t have to talk to each other in a loud voiceC. we can drink water from the polluted rivers and lakesD. people are making rules in order to fight pollutionC.Do you know why different animals or pests(昆虫)have their special colors? Colors in them seem to be used mainly to protect themselves.Some birds like eating locusts(蝗虫), but birds cannot easily catch them. Why? It is because locusts change their colors together with the change of colors of crops(庄稼). When crops are green, locusts look green. But as the harvest time comes, locusts change to the same brown color as crops have. Some other pests with different colors from plants are easily found and eaten by others. So they have to hide themselves for lives and appear only at night.If you study the animal life, you’ll find the main use of coloring is to protect themselves. Bears, lions and other animals move quietly through forests. They cannot be easily seen by hunters(猎人). This is because they have the colors much like the trees.Have you ever noticed an even stranger act? A kind of fish in the sea can send out a kind of very black liquid(液体)when it faces danger. While the liquid spread s over(散开), its enemies(敌人)cannot find it. And it immediately swims away. So it has lived up to now though it is not strong at all.( )41. From the passage we learn that locusts _______.A. are small animalsB. are easily found by birdsC. are dangerous to their enemiesD. change their colors to protect themselves ( )42. How can pests with different colors from plants keep out of danger?A. They run away quickly.B. They have the colors much like their enemies.C. They hide themselves by day and appear at night.D. They have to move quietly.( )43. Bears and lions can keep safe because _______.A. they have the colors much like the t reesB. they move quietlyC. they like brown and gray colorsD. they live in forests( )44. Why can the kind of fish live up to now?A. Because it is very strong.B. Because the liquid it sends out can help it escape from its enemiesC. Because the liquid it sends out can kill its enemies.D. Because it swims faster than any other fish.( )45. Which is the best title for this passage?A. The Change of Colors for Animals and PestsB. Colors of Different Animals and PestsC. The Main Use of Colors for Animals and PestsD. Some Animals and PestsD.Paper was first made in the year 105. It was made by a Chinese named Cai Lun. For over 500 years paper was made only in China. People in Japan learned of paper around the year 600. As years went by, people in other places began to make paper.The lead(铅)pencil is not made of lead. It is made of graphite(石墨). People found graphite in 1564. They thought it was a kind of lead. Today we still call pencils “lead pencils”. The first pencils were made by putting strings(线)around sticks of graphite.The first wooden pencils were made by Kasper Faber in Germany in 1761.Erasers like those we use today were first made in France by a man named Magellan in 1752. It was Hyman L. Lipman who first put eraser on the ends of pencils. And that is how the pencils came to be.( )46. How many years earlier was paper made in China than in Japan?A. About 100 years.B. About 400 years.C. More than 500 years.D. 495 years. ( )47. Germans made paper ______.A. earlier than JapanB. later than JapanC. as early as JapanD. as late as Japan ( )48. At first pencils were made of ______.A. woodB. leadC. sticksD. string and graphite( )49. Kasper Faber was ____.A. an EnglishmanB. a FrenchmanC. a GermanD. an American( )50. Which of the following st atements is NOT trueA. The first wooden pencils were made in Germany.B. Graphite isn’t a kind of lead.C. Paper was first made in China.D. Hyman L. Lipman made the first erasers.四、选词填空：10分much, arm, wait, see, when, spend, she, worry, have, grow Only Mother Love is true love. It gives everybody everything all his life. 51 you are still a baby, mother takes good care of you as much as possible. In your waking hours she always holds you in her 52 . When you are ill, she stops her work right now to look after you day and night and forgets about 53 . When you are 54 up day and day, she feels very happy. When you are old enough to go to school, mother still looks after you all the time. On cold winter days, she always tells you to put on 55 clothes. She always stands in the wind 56 for you back from school. When you hurry to leave home for school with little breakfast, she always feels 57 about you at home. She usually knows about your study and 58 much money on your school things. When you do well at school, the brightest smile will be 59 on her face.Mother is always ready to give everything she 60 to her children, not to receive. What true love that is in the world! We will remember Mother Love forever(永远).51. ________ 52. ________ 53. ________ 54. _________ 55. _______56. ________ 57. ________ 58. ________ 59. _________ 60. ________五、句型转换：10分61. The teacher told us, “The earth travels around the sun.” (改为间接引语)The teacher told us _____ the earth ______ around the sun.62. I’ve been skating for 2 hours.(对画线部分提问) _____ _____ _____ you been skating?63. They were doing their homework at six yesterday.(改为否定句)They ______ ______ their homework at six yesterday.64. He would like to play games with his friends. (同义句)He ____ ___ play games with his friends.65. Don’t be late again, ______ _______(反意疑问句)?六、书面表达：10分Julia和Jane是双胞胎．下面是她们上周末的时间安排表，请你描述一下她们上周末的生活。

北师大版八年级数学(下)总复习：各章知识点归纳总结及其巩固练习

八年级数学(下)总复习第一章整章水平测试一、填空题（每小题3分，共30分）1．若代数式2151--+t t 的值不小于-3，则t 的取值范围是_________． 2．不等式03≤-k x 的正数解是1，2，3，那么k 的取值范围是________．6．如果不等式组⎩⎨⎧><m x x 5有解，那么m 的取值范围是_______． 9．如果关于x 的不等式5)1(+<-a x a 和42<x 的解集相同，则a 的值为_____．二、选择题（每小题3分，共30分）4．如果0>>a b ，那么 [ ]．A ．b a 11->-B ．ba 11< C ．b a 11-<- D ．a b ->- 10．现用甲、乙两种运输车将46吨抗旱物资运往灾区，甲种运输车载重5吨，乙种运输车载重4吨，安排车辆不超过10辆，则甲种运输车至少应安排 [ ]．A ．4辆B ．5辆C ．6辆D ．7辆三、解答题（本大题，共40分）1．（本题8分）解下列不等式（组）：（1）1312523-+≥-x x ；第二章分解因式第二章整章水平测试一、精心选一选（每题4分，总共32分）1．下列各式中从左到右的变形属于分解因式的是（）.A.2(1)a a b a ab a +-=+-B.22(1)2a a a a --=--C.2249(23)(23)a b a b a b -+=-++D.121(2)x x x+=+ 2．把多项式－8a 2b 3c ＋16a 2b 2c 2－24a 3bc 3分解因式，应提的公因式是( )，A.－8a 2bcB. 2a 2b 2c 3C.－4abcD. 24a 3b 3c 3A ．22()()x y x y x y -=+-B ．2269(3)x x x ++=+C ．2()x xy x x y +=+D ．222()x y x y +=+5．把－6(x －y)2－3y(y －x)2分解因式，结果是( )．A.－3(x －y)2(2＋y)B. －(x －y)2(6－3y)C.3(x －y)2(y ＋2)D. 3(x －y)2(y －2)7．把代数式269mx mx m -+分解因式，下列结果中正确的是A ．2(3)m x +B ．(3)(3)m x x +-C ．2(4)m x -D ．2(3)m x -8.比较左、右两图的阴影部分面积，可以得到因式分解公式( ).A.))((22b a b a b a -+=-B.222)(ab a b a +=+C.2222)(b ab a b a +-=-D.)(2b a a ab a -=- 二、耐心填一填（每空4分，总共32分）8.如果a 2＋ma ＋121是一个完全平方式，那么m2.（5分）利用因式分解进行计算：0.746×136＋0.54×13.6＋27.2；（满分5分）若2m n -=-，求mn n m -+222的值？第三章分式1.在下列各式m a m x x b a x x a ,),1()3(,43,2,3222--÷++π中，是分式的有（） A.2个 B.3个 C.4个 D.5个2.要使分式733-x x 有意义，则x 的取值范围是（） A.x=37 B.x>37 C.x<37 D.x ≠=37 3.若分式4242--x x 的值为零，则x 等于（） A.2 B.-2 C.2± D.04.如果分式x+16 的值为正整数，则整数x 的值的个数是（） A.2个 B.3个 C.4个 D.5个 7.计算)1(1xx x x -÷-所得的正确结论（） A.11-x B.1 C.11+x D.-1 9.当x=33时，代数式)23(232xx x x x -+÷--的值是（） A.213- B.213+ C.313- D.313+ 二、填空题（每小题3分，共30分）15.使分式方程3232-=--x m x x 产生增根，m 的值为 .第五章数据的收集与处理（1）普查的定义：这种为了一定目的而对考察对象进行的全面调查，称为普查.（2）总体：其中所要考察对象的全体称为总体。

2023年新人教版八年级数学下册各章知识点及练习题

八年级数学下册知识点总结第十六章分式1. 分式旳定义：假如A 、B 表达两个整式，并且B 中具有字母，那么式子BA 叫做分式。

分式故意义旳条件是分母不为零，分式值为零旳条件分子为零且分母不为零2.分式旳基本性质：分式旳分子与分母同乘或除以一种不等于0旳整式，分式旳值不变。

（0≠C ）3.分式旳通分和约分：关键先是分解因式4.分式旳运算：分式乘法法则：分式乘分式，用分子旳积作为积旳分子，分母旳积作为分母。

分式除法法则：分式除以分式，把除式旳分子、分母颠倒位置后，与被除式相乘。

分式乘措施则：分式乘方要把分子、分母分别乘方。

,a b a b a c ad bc ad bcc c c bd bd bd bd±±±=±=±= 分式旳加减法则：同分母旳分式相加减，分母不变，把分子相加减。

异分母旳分式相加减，先通分，变为同分母分式，然后再加减混合运算:运算次序和此前同样。

能用运算率简算旳可用运算率简算。

5. 任何一种不等于零旳数旳零次幂等于1，即)0(10≠=a a ；当n 为正整数时，n naa 1=- （)0≠a 6.正整数指数幂运算性质也可以推广到整数指数幂．(m,n 是整数)（1）同底数旳幂旳乘法：nm n m a a a +=⋅；（2）幂旳乘方：mnnm aa =)(;（3）积旳乘方：nnn b a ab =)(；（4）同底数旳幂旳除法：nm nmaa a -=÷( a ≠0)；（5）商旳乘方：n nn ba b a =)(()；(b ≠0)7. 分式方程：含分式，并且分母中含未知数旳方程——分式方程。

解分式方程旳过程，实质上是将方程两边同乘以一种整式（最简公分母），把分式方程转化为整式方程。

bcad c d b a d c b a bd ac d c b a =⋅=÷=⋅;n n n ba b a =)(C B C A B A ⋅⋅=CB C A B A ÷÷=解分式方程时，方程两边同乘以最简公分母时，最简公分母有也许为０，这样就产生了增根，因此分式方程一定要验根。

八年级英语新目标下 unit1--unit10 ,复习专用。

Unit 1 复习小卷知识冲关1) My father ___________ ________ ____________ ___________up early. 我爸爸习惯于早起。

2) 他过去常骑自行车去上班，但现在他乘地铁（去上班）.He _________ ________ ________ his bike to work, but now he takes the subway.3) 刀子是用来割东西的.Knives are ___________ _________ __________ things.6. run out 用尽，用光，主语为物；run out of 用完，用尽，主语是人。

活学活用When the food ________________ ___________, they had to go out to find something to eat.When you __________ ___________ _________ your test time, you have to hand in your test papers at once.7. s o… that … 如此…以至于The math problem is so hard that I can’t work it out.so that 目的是I work hard so that I will have a good future.1) 那次聚会是如此让人激动以至于我永远不会忘记。

The party was _________ ________ ________ I would never forget it.2) 她是如此好的一位老师以至于所有的学生都喜欢她。

She is _______ __________ good teacher __________ all the students like her.3) 他们每天坚持锻炼目的是他们能够身体健康。

初二下总复习1-10单元复习题1

补全对话(一)A: Hello, may I speak to David?B: _________.(1)_____________A: Hi, David! This is Lin Tao speaking.B: Hi, Lin Tao . What’s up?A: What are you going to do next Sunday?B: ___________________(2)________. Do you have any ideas?A: Shall we go to the zoo? I hear there’s a dolphin show there.B: A dolphin show? Good idea! __________(3)__________ ?A: By bike.B: ____________(4)_____________?A: At half past nine.B: ____________(5)___________?A: Let’s meet outsid e the zoo gate.B: All right .See you then.（二）A: Hello, 6817502.B: Hello._________.(1)____________ ?A: Sorry, _____________(2)________ . (2) This is Jim’s mother, Mrs Green. Can I take a message?B: That’s very kind of you. This is David, Jim’s friend. I ask him for some Chinese stamps. He told me he had got some last week.A: OK. I will tell him about it. Would you like him to call you back later?B: Well, I won’t be at home today. My mother is ill, so I must go to the hospit al to look after her. Would you please ask him to ring me tomorrow morning?A: Oh, _____________(3)_________________。

八下数学复习题每一单元

八下数学复习题每一单元八下数学复习题每一单元数学是一门需要不断巩固和复习的学科，特别是在初中阶段。

八年级下册的数学课程内容丰富多样，包括了代数、几何、概率等多个方面。

为了帮助同学们更好地复习数学知识，本文将以每一单元为单位，介绍一些八下数学的复习题。

第一单元：有理数有理数是数学中的重要概念，它包括整数、正数、负数和分数。

在这一单元的复习中，可以从四则运算开始，例如计算：$(-\frac{1}{2})+(-\frac{3}{4})$。

同时，还可以通过解决实际问题来巩固有理数的应用，例如：小明用一块长为$\frac{3}{4}$米的绳子剪下$\frac{1}{3}$米，还剩下多长？第二单元：线性方程组线性方程组是解决多个未知数的方程组，它在数学和实际问题中都有广泛应用。

在这一单元的复习中，可以通过解方程组来巩固知识点。

例如，解方程组：$\begin{cases} 2x+y=5 \\ 3x-2y=4 \end{cases}$。

同时，还可以通过实际问题来应用线性方程组，例如：某商店出售两种商品，已知甲商品的价格是乙商品的2倍，总价为100元，求甲商品和乙商品的价格各是多少？第三单元：函数函数是数学中的重要概念，它描述了两个变量之间的关系。

在这一单元的复习中，可以通过绘制函数图像来巩固知识点。

例如，绘制函数$y=2x+1$的图像，并求出它的零点。

同时，还可以通过实际问题来应用函数，例如：某公司的销售额与广告费用之间的关系可以用函数$y=0.5x+100$表示，其中$x$为广告费用，$y$为销售额。

如果广告费用为200元，求销售额是多少？第四单元：平面图形的性质平面图形是几何学中的重要内容，它包括了多边形、三角形、四边形等。

在这一单元的复习中，可以通过计算图形的周长和面积来巩固知识点。

例如，计算一个边长为5cm的正方形的周长和面积。

同时，还可以通过解决实际问题来应用平面图形的性质，例如：一个矩形的长是宽的2倍，周长为24cm，求矩形的长和宽各是多少？第五单元：统计与概率统计与概率是数学中的实用内容，它包括了数据的收集、整理和分析，以及事件的可能性。

初中八年级语文下册单元及总复习题

初中八年级语文下册单元及总复习题第一单元：记叙文的基本知识复题：请根据以下情景，写出一篇记叙文。

情景1：你们班组织了一次春游活动，请你写一篇春游的记叙文。

情景2：你去参观了一个农家乐，请你写一篇对这次参观的记叙文。

第二单元：古代诗词的魅力复题：请写出你最喜欢的一首古代诗词，并解释你为什么喜欢它。

第三单元：人生格言对青少年的教育意义复题：列举三个你认为对青少年教育有积极影响的人生格言。

第四单元：故事篇章的布局和修辞手法复题：请写一篇300字的短篇故事，包含合理的布局和修辞手法。

第五单元：游记的写作技巧复题：请根据你最喜欢的一次旅行经历，写一篇有关该旅行的游记。

总复题1. 解析以下词语的意思：自卑、自豪、虚荣、真诚、随便、揣摩。

2. 试写一段对某个事物进行描写的文字，注意使用生动形象的词语。

3. 选择一个你喜欢的动物，简单描述其特征和性。

4. 解释以下成语的意思：望尘莫及、狼吞虎咽、手舞足蹈、高兴异常、无微不至。

5. 同学们通常在什么情况下会感到自豪？请用一个例子来说明。

6. 请回忆一下，你曾经读过的一本书的情节和人物，并简要介绍故事的内容。

7. 你认为什么样的人更容易被别人喜欢？请简要说明理由。

8. 每个人都有自己的梦想，请简要介绍你的梦想，并说明你为实现梦想做了哪些努力。

9. 你觉得什么样的品质是一个人成功的关键？为什么？10. 请从音乐、绘画、运动这三个方面，选择一个你最喜欢的，并简要说明喜欢的原因。

以上是初中八年级语文下册单元及总复习题。

希望同学们认真复习，加油！。

初二(下)总复习(十)

初二(下)总复习(十)1. 如图，梯子AB斜靠在墙上，∠ACB=90°，AB=5米，BC=4米，当点B下滑到点B′时，点A向左平移到点A′。

设BB′=x米(0<x<4)，AA′=y米。

(1)用含x的代数式表示y；(2)当x为何值时，点B下滑的距离与点A向左平移的距离相等？(3)请你对x再取几个值，计算出对应的y值，并比较对应的y值与x值的大小(y值可以用精确到0.01的近似数表示，也可用无理数表示)。

(4)根据第(1) ~ (3)题的计算，还可以结合画图、观察，推测y与x的大小关系及对应的x的取值范围。

2. 2001年亚洲铁人三项赛在徐州市风光秀丽的云龙湖畔举行。

比赛程序是：运动员先同时下水游泳1.5千米到第一换项点，在第一换项点整理服装后，接着骑自行车行40千米到第二换项点，再跑步10千米到终点。

下表是2001年亚洲铁人三项赛女子组(19岁以下)三名运动员在比赛中的成绩（游泳成绩即游泳所用时间，其它类推，表内时间单位为秒）运动员号码游泳成绩第一换项点所用时间自行车成绩第二换项点所用时间长跑成绩191 1997 75 4927 40 3220 194 1503 110 5686 57 3652 195 1354 74 5351 44 3195 (1)填空（精确到0.01）：第191号运动员骑自行车的平均速度是米/秒；第194号运动员骑自行车的平均速度是米/秒；第195号运动员骑自行车的平均速度是米/秒；(2)如果运动员骑自行车都是匀速的，那么在骑自行车的途中，191号运动员会追上195号或194号吗？如果会，那么追上时离第一换项点有多少米（精确到0.01）？如果不会，为什么？(3)如果长跑也都是匀速的，那么在长跑途中这三名运动员中有可能某人追上某人吗？为什么？3.据有关部门统计:20世纪初全世界共有哺乳类和鸟类动物约13000种,由于环境等到因素的影响,到20世纪末这两类动物种数共灭绝约1.9%,其中哺乳类动物灭绝约3.0%,鸟类动物灭绝约1.5%.(1)问20世纪初哺乳类动物和鸟类动物各有多少种?(2)现在人们越来越意识到保护动物就是保护人类自己,到本世纪末,如果要把哺乳类动物的灭绝种数控制在0.9%以内,其中哺乳类动物灭绝的咱数与鸟类动物灭绝的种数之比约为6:7.为实现这个目标,鸟类灭绝不能超过多少种?(本题所求结果均精确到十位)4．为了能有效地使用电力资源，宁波市电业局从2002年1月起进行居民峰谷用电试点，每天8：00至22：00用电每千瓦时0．5 6元（“峰电”价），22：00至次日8：00每千瓦时0．28元(“谷电”价)，而目前不使用“峰谷”电的居民用电每千瓦时0．53元．(1）一居民家庭在某月使用“峰谷”电后，付电费95．2元，经测算比不使用“峰谷”电节约10．8元，问该家庭当月使用“峰电”和“谷电”各多少千瓦时？(2)当“峰电”用量不超过每月总用电量的百分之几时，使用“峰谷”电合算？（精确到1％）5.某市电信局现有600部已申请装机的固定电话沿待装机，此外每天还有新申请装机的电话也待装机，设每天新申请装机的固定电话部数相同，每个电话装机小组每天安装的固定电话部数也相同，若安排3个装机小组，恰好60天可将待装固定电话装机完毕；若安排5个装机小组，恰好20天可将待装固定电话装机完毕。

八年级数学下册各章节复习题(分章节题)精品

《十六章分式》复习考点一识别出分式分式的定义：式子为BA的形式.A 、B 都是整式，并且B 中都含有字母 1.下列各式中是分式的有。

①9x+4， ②x 7 , ③209y +, ④54-m , ⑤238y y -， ⑥91-x ⑦y x 72+ 2、下列各式：()xx x x y x x x 2225 ,1,2 ,34 ,151+---π其中分式共有（）个。

A 、2B 、3C 、4D 、54．代数式21,,,13x x a x x x π+中，分式的个数是（） A ．1 B ．2 C ．3 D ．4考点二指出分式有意义或无意义时字母的取值范围知识分式B A 有意义只要满足，若分式BA无意义只要满足。

1.当x______时，11+x 有意义 ;当x____________时，分式31x x --无意义; 2.当x ＝______时，分式11x x +-有意义；当x ＝________时，分式31－x 没有意义．当x 时，分式x-13无意义；3、当x 为任意实数时，下列分式一定有意义的是（）A ．212-x B ．122+x C ．22x D ．21+x4.写一个分式，使它满足当x ≠4时有意义。

_______________________________考点三指出分式的值为零时字母的取值知识分式BA＝0必须同时满足两个条件① ② 1.若分式112+-x x 的值为零,则x 的值是( )A.1或-1B.1C.-1D.02.当x_______时，分式31x x +-的值为零; 当x ＝______时，分式2x x x -的值为0．3.当m=_________时，分式23)3)(1(2+---m m m m 的值为0。

4.若分式||55y y--的值等于0，则y= __________ ． 5.若分式13-x的值为整数，则整数x=6.当x 时，分式392--x x 的值为零. 考点四分式的基本性质知识一个分式的分子、分母同乘（或除以）一个不为0的，分式的值不变。

苏科版八年级下册数学总复习

苏科版八年级下册数学总复习一、选择题1．“明天会下雨”这是一个（）A ．必然事件B ．不可能事件C ．随机事件D ．以上说法都不对 2．如图，在四边形ABCD 中，//AB CD ，要使四边形ABCD 是平行四边形，下列可添加的条件不正确的是（）A ．AB CD ＝ B ．//AD BC C ．A C ∠∠＝D ．AD BC ＝3．已知12x <≤ ，则23(2)x x -+-的值为（）A ．2 x - 5B ．—2C ．5 - 2 xD ．24．已知关于x 的分式方程22x m x +-＝3的解是5，则m 的值为（） A ．3 B ．﹣2C ．﹣1D ．8 5．下列式子为最简二次根式的是（）A ．22a b +B ．2aC ．12aD ．126．如图，▱ABCD 的周长为22m ，对角线AC 、BD 交于点O ，过点O 与AC 垂直的直线交边AD 于点E ，则△CDE 的周长为（）A ．8cmB ．9cmC ．10cmD ．11cm7．下列图形中，既是中心对称图形又是轴对称图形的是（）A ．B ．C ．D ．8．从某市5000名初一学生中，随机抽取100名学生，测得他们的身高数据，得到一个样本，则这个样本数据的平均数、中位数、众数、方差四个统计量中，服装厂最感兴趣的是（）A ．平均数B ．中位数C ．众数D ．方差9．如图，正方形ABCD 中，点E 、F 、H 分别是AB 、BC 、CD 的中点，CE 、DF 交于G ，连接AG 、HG ，下列结论：①CE ⊥DF ；②AG=AD ；③∠CHG=∠DAG ；④HG=12AD ．其中正确的有( )A ．① ②B ．① ② ④C ．① ③ ④D ．① ② ③ ④ 10．如图，是一组由菱形和矩形组成的图案，第1个图中菱形的面积为S （S 为常数），第2个图中阴影部分是由连接菱形各边中点得到的矩形和再连接矩形各边中点得到的菱形产生的，依此类推…，则第2020个图中阴影部分的面积可以用含S 的代数式表示为（）（S ≥2且S 是正整数）A ．20184SB ．20194SC ．20204SD ．20214S二、填空题11．“一只不透明的袋子共装有3个小球，它们的标号分别为1，2，3，从中摸出1个小球，标号为“4”，这个事件是______．（填“必然事件”、“不可能事件”或“随机事件”）12．不透明的袋子里装有6只红球，1只白球，这些球除颜色外都相同．搅匀后从中任意摸出1只球．摸出的是红球的可能性_____摸出的是白球的可能性（填“大于”、“小于”或“等于”）．13．已知a ，b 是一元二次方程x 2﹣2x ﹣2020＝0的两个根，则a 2+2b ﹣3的值等于_____．14．某气球内充满了一定量的气体，当温度不变时，气球内气体的气压p （kPa ）是气体体积()3m V 的反比例函数，其图像如图所示.则其函数解析式为_________.15．如图，等腰梯形ABCD 中，//AD BC ，1AB DC ==，BD 平分ABC ∠，BD CD ⊥，则AD BC +等于_________.16．如图是某市连续5天的天气情况，最大的日温差是________℃．17．如图，在矩形ABCD 中，AC 、BD 交于点O ，DE ⊥AC 于点E ，若∠AOD ＝110°，则∠CDE ＝________°．18．若点()23，在反比例函数k y x =的图象上，则k 的值为________． 19．若关于x 的分式方程233x a x x +--＝2a 无解，则a 的值为_____． 20．如图，菱形ABCD 中，对角线AC 、BD 相交于点O ，H 为AB 边中点，菱形ABCD 的周长为24，则OH 的长等于___．三、解答题21．先化简：22241a a a a a+--÷-，再从﹣1、0、1、2中选一个你喜欢的数作为a 的值代入求值．22．已知：如图，在 ABCD 中，点E 、F 分别在AD 、BC 上，且∠ABE ＝∠CDF ．求证：四边形BFDE是平行四边形．23．如图所示的正方形网格中，△ABC的顶点均在格点上，请在所给直角坐标系中按要求画图和解答下列问题：（1）以A点为旋转中心，将△ABC绕点A顺时针旋转90°得△AB1C1，画出△AB1C1．（2）作出△ABC关于坐标原点O成中心对称的△A2B2C2．（3）作出点C关于x轴的对称点P．若点P向右平移x（x取整数）个单位长度后落在△A2B2C2的内部，请直接写出x的值．24．如图，在平面直角坐标系中，△ABC的三个顶点坐标分别为A（﹣3，﹣1）、B（﹣1，0）、C（0，﹣3）（1）点A关于坐标原点O对称的点的坐标为．（2）将△ABC绕点C顺时针旋转90°，画出旋转后得到的△A1B1C，A1A的长为．25．如图，∠MON＝90°，正方形ABCD的顶点A、B分别在OM、ON上，AB＝13，OB＝5，E为AC上一点，且∠EBC＝∠CBN，直线DE与ON交于点F．（1）求证BE＝DE；（2）判断DF与ON的位置关系，并说明理由；（3）△BEF的周长为．26．如图，已知一次函数y ＝x +2的图象与x 轴、y 轴分别交于点A ，B 两点，且与反比例函数y ＝m x的图象在第一象限交于点C ，CD ⊥x 轴于点D ，且OA ＝OD ．（1）求点A 的坐标和m 的值；（2）点P 是反比例函数y ＝m x 在第一象限的图象上的动点，若S △CDP ＝2，求点P 的坐标．27．如图1，在正方形ABCD 中，点E 是边AB 上的一个动点（点E 与点A ，B 不重合）连接CE ，过点B 作BF ⊥CE 于点G ，交AD 于点F ．（1）求证：△ABF ≌△BCE ；（2）如图2，连接EF 、CF ，若CE ＝8，求四边形BEFC 的面积；（3）如图3，当点E 运动到AB 中点时，连接DG ，求证：DC ＝DG ．28．如图，点P 为ABC ∆的BC 边的中点，分别以AB 、AC 为斜边作Rt ABD ∆和Rt ACE ∆，且BAD CAE α∠=∠=，DPE β∠=．（1）求证：PD PE =．（2）探究：α与β的数量关系，并证明你的结论．【参考答案】***试卷处理标记，请不要删除一、选择题1．C解析：C【分析】在一定条件下，可能发生也可能不发生的事件，称为随机事件．据此可得．【详解】解：“明天会下雨”这是一个随机事件，故选：C ．【点晴】本题主要考查随机事件，解题的关键是掌握随机事件的概念：在一定条件下，可能发生也可能不发生的事件，称为随机事件．2．D解析：D【分析】平行四边形的五种判定方法分别是:两组对边分别平行的四边形是平行四边形；两组对边分别相等的四边形是平行四边形；一组对边平行且相等的四边形是平行四边形；两组对角分别相等的四边形是平行四边形；对角线互相平分的四边形是平行四边形．根据平行四边形的判定,逐个验证即可．【详解】解：A.∵//AB CD ， AB CD =∴四边形ABCD 是平行四边形（一组对边平行且相等的四边形是平行四边形），故本选项不符合题意；B.∵//AB CD ， //AD BC∴四边形ABCD 是平行四边形（两组对边分别平行的四边形是平行四边形），故本选项不符合题意；C.∵//AB CD∴180C D ∠+∠=︒∵A C ∠=∠∴180A D +=︒∠∠∴//AD BC∴四边形ABCD 是平行四边形（两组对边分别平行的四边形是平行四边形），故本选项不符合题意；D.若添加AD BC =不一定是平行四边形，如图：四边形ABCD 为等腰梯形，故本选项符合题意．故选：D【点睛】本题考查了平行四边形的判定，是开放题，可以针对平行四边形的各种判定方法，结合给出相应的条件进行判定．3．C解析：C【分析】结合1 < x ≤ 2 ，根据绝对值和二次根式的进行计算，即可得到答案．【详解】因为1 < x ≤ 2 ，所以23(2)x x -+-32x x -+-= 5 - 2 x.故选择C ．【点睛】本题考查不等式、绝对值和二次根式，解题的关键是掌握不等式、绝对值和二次根式．4．C解析：C【分析】将x ＝5代入分式方程中进行求解即可．【详解】把x ＝5代入关于x 的分式方程22x m x +-＝3得：25352m ⨯+=-，解得：m ＝﹣1，故选：C ．【点睛】本题考查分式方程的解，一般直接将解代入分式方程进行求解．5．A解析：A【分析】判断一个二次根式是否为最简二次根式主要方法是根据最简二次根式的定义进行，或直观地观察被开方数的每一个因数（或因式）的指数都小于根指数2，且被开方数中不含有分母，被开方数是多项式时要先因式分解后再观察．【详解】AB|a|，可以化简，故不是最简二次根式；C==，可以化简，故不是最简二次根式；D2故选：A．【点睛】本题考查最简二次根式的定义，最简二次根式必须满足两个条件：被开方数不含分母；被开方数不含能开得尽方的因数或因式．6．D解析：D【解析】【分析】由平行四边形的性质可得AB＝CD，AD＝BC，AO＝CO，可得AD+CD＝11cm，由线段垂直平分线的性质可得AE＝CE，即可求△CDE的周长＝CE+DE+CD＝AE+DE+CD＝AD+CD＝11cm．【详解】解：∵四边形ABCD是平行四边形∴AB＝CD，AD＝BC，AO＝CO，又∵EO⊥AC，∴AE＝CE，∵▱ABCD的周长为22cm，∴2（AD+CD）＝22cm∴AD+CD＝11cm∴△CDE的周长＝CE+DE+CD＝AE+DE+CD＝AD+CD＝11cm故选：D．【点睛】本题考查了平行四边形的性质，线段垂直平分线的性质，熟练运用平行四边形的性质是本题的关键．7．A解析：A【分析】直接利用轴对称图形和中心对称图形的概念求解．【详解】解：A、是中心对称图形，也是轴对称图形，故此选项符合题意；B、不是中心对称图形，是轴对称图形，故此选项不合题意；C、是中心对称图形，不是轴对称图形，故此选项不合题意；D、不是中心对称图形，是轴对称图形，故此选项不合题意；故选：A．【点睛】此题主要考查了中心对称与轴对称的概念：轴对称的关键是寻找对称轴，两边图象折叠后可重合，中心对称是要寻找对称中心，旋转180°后与原图重合．8．C解析：C【解析】【分析】服装厂最感兴趣的是哪种尺码的服装售量较多，也就是需要参照指标众数．【详解】由于众数是数据中出现次数最多的数，故服装厂最感兴趣的指标是众数．故选(C)【点睛】本题考查统计量的选择，解题的关键是区分平均数、中位数、众数和方差的概念与意义进行解答；9．D解析：D【详解】∵四边形ABCD是正方形，∴AB=BC=CD=AD，∠B=∠BCD=90°，∵点E、F、H分别是AB、BC、CD的中点，∴△BCE≌△CDF，∴∠ECB=∠CDF，∵∠BCE+∠ECD=90°，∴∠ECD+∠CDF=90°，∴∠CGD=90°，∴CE⊥DF，故①正确；在Rt△CGD中，H是CD边的中点，∴HG=12CD=12AD，故④正确；连接AH，同理可得：AH⊥DF，∵HG=HD=12CD ， ∴DK=GK ，∴AH 垂直平分DG ，∴AG=AD ，故②正确；∴∠DAG=2∠DAH ，同理：△ADH ≌△DCF ，∴∠DAH=∠CDF ，∵GH=DH ，∴∠HDG=∠HGD ，∴∠GHC=∠HDG+∠HGD=2∠CDF ，∴∠CHG=∠DAG ．故③正确．故选D ．【点睛】运用了正方形的性质，全等三角形的判定与性质，等腰三角形的性质以及垂直平分线的性质等知识．此题综合性很强，难度较大，解题的关键是注意数形结合思想的应用．10．B解析：B【分析】观察图形发现第2个图形中的阴影部分的面积为S 4，第3个阴影部分的面积为16S ，依此类推，得到第n 个图形的阴影部分的面积即可．【详解】解：观察图形发现：第2个图形中的阴影部分的面积为S 4，第3个图形中的阴影部分的面积为16S ， …第n 个图形中的阴影部分的面积为14n S，故第2020个图中阴影部分的面积可以用含S 的代数式表示为20194S ．故选：B ．【点睛】本题考查了图形的变化类问题，解题的关键是仔细的观察图形，找到规律用通项公式表示出来．二、填空题11．不可能事件．【解析】根据题意，可知这个袋子中有3个数字，抽取一个球时不可能抽到数字4，所以是不可能事件.故答案为不可能事件.解析：不可能事件．【解析】根据题意，可知这个袋子中有3个数字，抽取一个球时不可能抽到数字4，所以是不可能事件.故答案为不可能事件.12．大于【分析】分别计算出摸出的是红球和白球的概率，然后根据概率的大小进行判断．【详解】解：从中任意摸出1只球．摸出的是红球的概率＝，摸出的是白球的概率＝，所以摸出的是红球的可能性大于摸出的解析：大于【分析】分别计算出摸出的是红球和白球的概率，然后根据概率的大小进行判断．【详解】解：从中任意摸出1只球．摸出的是红球的概率＝67，摸出的是白球的概率＝17，所以摸出的是红球的可能性大于摸出的是白球的可能性．故答案为：大于．【点睛】本题考查的是概率的意义，以及求简单随机事件的概率，掌握以上知识是解题的关键．13．2021【分析】根据一元二次方程的根与系数的关系得出，再结合原方程可知，由此进一步求解即可.【详解】∵a是一元二次方程的一个根，∴，再由根与系数的关系可知：，＝a2−解析：2021【分析】根据一元二次方程的根与系数的关系得出2a b +=，再结合原方程可知222020a a -=，由此进一步求解即可.【详解】∵a 是一元二次方程的一个根，∴222020a a -=，再由根与系数的关系可知：2a b +=，∴a 2+2b −3＝a 2−2a +2a +2b −3，＝2020+2(a +b )−3＝2020+2×2−3＝2021，故答案为：2021.【点睛】本题主要考查了一元二次方程的性质与根与系数的关系的运用，熟练掌握相关概念是解题关键.14．【分析】根据“气压×体积＝常数”可知：先求得常数的值，再表示出气体体积V 和气压p 的函数解析式．【详解】设，那么点（1.6，60）在此函数解析式上，则k ＝1.6×60＝96，∴．故答案为：解析：96P V=【分析】根据“气压×体积＝常数”可知：先求得常数的值，再表示出气体体积V 和气压p 的函数解析式．【详解】设k P V=，那么点（1.6，60）在此函数解析式上，则k ＝1.6×60＝96， ∴96P V=．故答案为：96P V =．解答该类问题的关键是确定两个变量之间的函数关系，然后利用待定系数法求出它们的关系式．15．3【分析】由，平分，易证得是等腰三角形，即可求得，又由四边形是等腰梯形，易证得，然后由，根据直角三角形的两锐角互余，即可求得，则可求得的值，继而求得的值.【详解】解：∵，，∴，，∵平分，解析：3【分析】由//AD BC ，BD 平分ABC ∠，易证得ABD ∆是等腰三角形，即可求得1AD AB ==，又由四边形ABCD 是等腰梯形，易证得2C DBC ∠=∠，然后由BD CD ⊥，根据直角三角形的两锐角互余，即可求得30DBC ∠=︒，则可求得BC 的值，继而求得AD BC +的值.【详解】解：∵//AD BC ，AB DC =，∴C ABC ∠=∠，ADB DBC ∠=∠，∵BD 平分ABC ∠，∴2ABC DBC ∠=∠，ABD DBC ∠=∠，∴ABD ADB ∠=∠，∴1AD AB ==，∴2C DBC ∠=∠，∵BD CD ⊥，∴90BDC ∠=︒，∵三角形内角和为180°，∴90DBC C ∠+∠=︒，∴260C DBC ∠=∠=︒，∴2212BC CD ==⨯=，∴123AD BC +=+=.故答案为：3．【点睛】本题主要考查对勾股定理，含30度角的直角三角形，等腰三角形的性质和判定，平行线的性质，等腰梯形的性质等知识点的理解和掌握，综合运用这些性质进行推理和计算是解此题的关键．【分析】根据图象找出气温差距最大的一天，然后计算温差即可．【详解】由图可得气温差距最大的一天为5月28日，温差为：25-15=10，故答案为：10．【点睛】本题考查了有理数减法的解析：10【分析】根据图象找出气温差距最大的一天，然后计算温差即可．【详解】由图可得气温差距最大的一天为5月28日，温差为：25-15=10，故答案为：10．【点睛】本题考查了有理数减法的实际应用，根据图象找出温差最大的一天是解题关键．17．35【分析】先根据三角形外角的性质和矩形的性质得到∠OCD的度数，再根据DE⊥AC即可得到∠CDE的度数．【详解】∵∠AOD＝110°，∴∠ODC+∠OCD=110°，∵四边形ABCD是解析：35【分析】先根据三角形外角的性质和矩形的性质得到∠OCD的度数，再根据DE⊥AC即可得到∠CDE 的度数．【详解】∵∠AOD＝110°，∴∠ODC+∠OCD=110°，∵四边形ABCD是矩形，∴OC=OD，∴∠ODC=∠OCD=55°，又∵DE⊥AC，∴∠CDE=180°-∠OCD-∠DEC=180°-55°-90°=35°，故答案为：35．【点睛】本题考查了矩形的性质，三角形内角和，三角形外角的性质，掌握知识点是解题关键．18．6【详解】解：由题意知：k=3×2=6故答案为：6解析：6【详解】解：由题意知：k=3×2=6故答案为：619．5或1.5【分析】先直接解分式方程，整理得：（1﹣2a）x＝﹣4a，再分类讨论①当1﹣2a＝0时，方程无解，故a＝0.5；②当1﹣2a≠0时，x＝＝3时，分式方程无解，则a＝1.5 . 【详解】解析：5或1.5【分析】先直接解分式方程，整理得：（1﹣2a）x＝﹣4a，再分类讨论①当1﹣2a＝0时，方程无解，故a＝0.5；②当1﹣2a≠0时，x＝421aa-＝3时，分式方程无解，则a＝1.5 .【详解】解：2233x aax x+=--，去分母得：x﹣2a＝2a（x﹣3），整理得：（1﹣2a）x＝﹣4a，当1﹣2a＝0时，方程无解，故a＝0.5；当1﹣2a≠0时，x＝421aa-＝3时，分式方程无解，则a＝1.5，则a的值为0.5或1.5．故答案为：0.5或1.5．【点睛】本题主要考查了当分式方程无意义时，求字母的值.值得引起注意的是，当分式方程化为整式方程（1﹣2a）x＝﹣4a时，一定要分1-2a=0和1-2a≠0两种情况，来分别求m的值.20．【分析】根据已知可求得菱形的边长，再根据对角线互相垂直平分，H为AB的中点，从而求得OH的长．【详解】∵菱形ABCD 的周长等于24，∴AB==6，∵四边形ABCD 是菱形，∴AC ⊥BD ，解析：【分析】根据已知可求得菱形的边长，再根据对角线互相垂直平分，H 为AB 的中点，从而求得OH 的长．【详解】∵菱形ABCD 的周长等于24，∴AB =244=6， ∵四边形ABCD 是菱形，∴AC ⊥BD ，∵H 为AB 边中点，∴在Rt △AOB 中，OH 为斜边上的中线，∴OH =12AB =3．故答案为：3．【点睛】本题主要考查了菱形的性质，直角三角形斜边上的中线的性质，掌握“直角三角形中，斜边上的中线等于斜边的一半”是正确解答本题的关键．三、解答题21．1a 2--，当1a =-时，原式1=3【分析】本题根据分式的除法和减法运算法则，结合平方差以及提公因式法将题目化简，然后从1-、0、1、2中选一个使得原分式有意义的值代入化简后的式子即可解答本题．【详解】原式2(1)1111(2)(2)22a a a a a a a a a +--=-⨯=-=-+---，由已知得：若使原分式有意义，需满足0a ≠，20a a -≠，240a -≠，即当0a =、1、2、2-时原分式无意义，故当1a =-时，原式11123=-=--．【点睛】本题考查分式的化简求值，解题关键在于对平方差、完全平方公式等运算法则的运用，其次注意计算仔细即可．22．见解析【分析】先根据平行四边形的性质，得出ED∥BF，再结合已知条件∠ABE＝∠CDF推断出EB∥DF，即可证明．【详解】证明：∵四边形ABCD为平行四边形，∴AD∥BC，∠ABC＝∠ADC，∴∠ADF＝∠DFC，ED∥BF，∵∠ABE＝∠CDF，∴∠ABC－∠ABE＝∠ADC－∠CDF，即∠EBC＝∠ADF，∴∠EBC＝∠DFC，∴EB∥DF，∴四边形BFDE是平行四边形．【点睛】本题考查了平行四边形的性质和平行四边形的判定定理，掌握知识点是解题关键．23．（1）图见解析；（2）图见解析；（3）x的值为6或7．【分析】（1）分别作出B、C的对应点B1，C1即可解决问题；（2）分别作出A、B、C的对应点A2、B2、C2即可解决问题；（3）观察图形即可解决问题.【详解】（1）作图如下：△AB1C1即为所求；（2）作图如下：△A2B2C2即为所求；（3）P点如图，x的值为6或7.【点睛】本题考查旋转、中心对称图形，格点作图，熟练掌握对称、旋转及网格作图的特征是解题关键.24．（1）（3，1）；（2）作图见解析；26．【分析】（1）根据对称性即可得点A关于坐标原点O对称的点的坐标；（2）根据旋转的性质即可将△ABC绕点C顺时针旋转90°，画出旋转后得到的△A1B1C，进而可得A1A的长．【详解】（1）∵A（﹣3，﹣1），∴点A关于坐标原点O对称的点的坐标为（3，1）．故答案为：（3，1）；（2）如图，△A1B1C即为所求，A1A221526．26【点睛】本题考查了作图-旋转变换，解决本题的关键是掌握旋转的性质．25．（1）见解析；（2）DF⊥ON，理由见解析；（3）24【分析】（1）根据正方形的性质证明△BCE≌△DCE即可；（2）由第一题所得条件和已知条件可推出∠EDC＝∠CBN，再利用90°的代换即可证明；（3）过D点作DG垂直于OM，交点为G，结合已知条件推出DF和BF的长，再根据第一题结论得出△BEF的周长等于DF加BF即可得出答案．【详解】解：（1）证明：∵四边形ABCD正方形，∴CA平分∠BCD，BC＝DC，∴∠BCE＝∠DCE＝45°，∵CE＝CE，∴△BCE≌△DCE（SAS）；∴BE＝DE；（2）DF⊥ON，理由如下：∵△BCE≌△DCE，∴∠EBC＝∠EDC，∵∠EBC＝∠CBN，∴∠EDC＝∠CBN，∵∠EDC+∠1＝90°，∠1＝∠2，∴∠2+∠CBN＝90°，∴∠EFB＝90°，即DF⊥ON；（3）过D点作DG垂直于OM，交点为G，∵四边形ABCD是正方形，∴AD=AB，∠BAD=90°，∴∠DAG+∠BAO=90°，∵∠ABO+∠BAO=90°，∴∠DAG=∠ABO，又∵∠MON=90°，DG⊥OM，∴△ADG≌△ABO，∴DM=AO，GA=OB=5，∵AB=13，OB=5，根据勾股定理可得AO=12，由（2）可知DF⊥ON，又∵∠MON=90°，DG⊥OM，∴四边形OFDM是矩形，∴OF=DG=AO=12，DF=OM=17，由（1）可知BE＝DE，∴△BEF 的周长=DF+BF=17+（12-5）=24．【点睛】本题考查了正方形的性质，全等三角形的判定和性质，矩形的判定，掌握知识点是解题关键．26．（1）（-2,0）；8 （2）（1，8）或（3，83）【分析】（1）根据待定系数法就可以求出函数的解析式；（2）1||2CDP P C S CD x x =⨯⨯-△，即可求解．【详解】解：（1）对于一次函数2y x =+，令0x =，则2y =，令0y =，则2x =-，故点A 、B 的坐标分别为(2,0)-、(0,2)， OA OD =，故点(2,0)D ，则点C 的横坐标为2，当2x =时，24y x =+=，故点(2,4)C ，将点C 的坐标代入反比例函数表达式得：42m =，解得：8m =，故点A 的坐标为(2,0)-，8m =；（2）1142222CDP P C P S CD x x x =⨯⨯-=⨯⨯-=，解得：3P x =或1，故点P 的坐标为(1,8)或8(3,)3．【点睛】本题考查了反比例函数与一次函数的交点，当有两个函数的时候，着重使用一次函数，体现了方程思想，综合性较强．27．（1）见解析；（2）32；（3）见解析【分析】（1）根据同角的余角相等得到∠GCB ＝∠FBA ，利用ASA 定理证明△ABF ≌△BCE ；（2）根据全等三角形的性质得到BF ＝CE ＝8，根据三角形的面积公式计算，得到答案；（3）作DH ⊥CE ，设AB ＝CD ＝BC ＝2a ，根据勾股定理用a 表示出CE ，根据三角形的面积公式求出BG ，根据勾股定理求出CG ，证明△CHD ≌△BGC ，得到CH ＝BG ，证明CH ＝GH ，根据线段垂直平分线的性质证明结论．【详解】（1）证明：∵BF ⊥CE ，∴∠CGB ＝90°，∴∠GCB +∠CBG ＝90，∵四边形ABCD 是正方形，∴∠CBE ＝90°＝∠A ，BC ＝AB ，∴∠FBA +∠CBG ＝90，∴∠GCB ＝∠FBA ，在△ABF 和△BCE 中，A CBE AB BCABF BCE ⎧∠=∠⎪=⎨⎪∠=∠⎩， ∴△ABF ≌△BCE （ASA ）；（2）解：∵△ABF ≌△BCE ，∴BF ＝CE ＝8，∴四边形BEFC 的面积＝△BCE 的面积+△FCE 的面积＝12×CE ×FG +12×CE ×BG ＝12×CE ×（FG +BG ）＝12×CE ×BF ＝12×8×8 ＝32；（3）证明：如图3，过点D 作DH ⊥CE 于H ，设AB ＝CD ＝BC ＝2a ，∵点E 是AB 的中点，∴EA ＝EB ＝12AB ＝a ， ∴CE=，在Rt △CEB 中，12BG •CE ＝12CB •EB ， ∴BG＝5CB EB a CE ⋅=， ∴CG5a =， ∵∠DCE +∠BCE ＝90°，∠CBF +∠BCE ＝90°，∴∠DCE ＝∠CBF ，∵CD ＝BC ，∠CHD ＝∠CGB ＝90°，∴△CHD ≌△BGC （AAS ），∴CH ＝BGa ，∴GH ＝CG ﹣CH ＝25a ＝CH ， ∵CH ＝GH ，DH ⊥CE ，∴CD ＝GD ；【点睛】本题通过正方形动点问题引入，考查了三角形全等、勾股定理和垂直平分线定理的应用．28．（1）详见解析；（2）2180αβ+=︒，证明见解析．【分析】（1）如图，分别取AB 、AC 的中点M 、N ，连接DM 、PM 、PN 、NE ，根据三角形的中位线定理和直角三角形的性质可得PM NE =，DM PN =，根据等腰三角形的性质、三角形的外角性质和已知条件可得BMD CNE ∠=∠，根据平行线的性质可得BMP BAC ∠=∠=CNP ∠，进而可得DMP PNE ∠=∠，于是可根据SAS 证明MDP NPE ∆≅∆，从而可得结论；（2）根据平行线的性质可得BMP MPN ∠=∠，根据全等三角形的性质可得EPN MDP ∠=∠，然后在DMP ∆中利用三角形的内角和定理和等量代换即可得出结论．【详解】（1）证明：如图，分别取AB 、AC 的中点M 、N ，连接DM 、PM 、PN 、NE ．点P 为ABC ∆的边BC 的中点，∴12PM AC =， NE 为Rt AEC ∆斜边上的中线，∴12NE AN AC ==， PM NE ∴=，同理可得：DM PN =，12DM AM AB ==， ADM BAD ∴∠=∠，2BMD BAD ∴∠=∠，同理，2CNE CAE ∠=∠，又BAD CAE α∠=∠=，BMD CNE ∴∠=∠，又PM 、PN 都是ABC ∆的中位线，//PM AC ∴，//PN AB ，BMP BAC ∴∠=∠，CNP BAC ∠=∠，BMP CNP ∴∠=∠，∴DMP PNE ∠=∠，MDP NPE ∴∆≅∆(SAS)，PD PE ∴=；（2）解：α与β的数量关系是：2180αβ+=︒；证明：//PN AB ，BMP MPN ∴∠=∠，∵MDP NPE ∆≅∆，EPN MDP ∴∠=∠，在DMP ∆中，∵180MDP DPM DMP ∠+∠+∠=︒，∴180MDP DPM DMB PMB ∠+∠+∠+∠=︒，而22DMB BAD α∠=∠=，2180EPN DPM MPN α∴∠+∠++∠=︒，DPE DPM MPN EPN β∠=∠+∠+∠=， 2180αβ∴+=︒．【点睛】本题考查了三角形的中位线定理、全等三角形的判定和性质、直角三角形的性质、等腰三角形的性质、平行线的性质、三角形的外角性质和三角形的内角和定理等知识，具有一定的综合性，正确添加辅助线、熟练掌握上述知识是解题的关键．。

八年级下全册复习

一、选择题（单选）1．已知△ABC中，∠ABC=45º，F是高AD和BE的交点，CD=4，则线段DF的长度为（B ）A. 22B. 4C. 32D. 42解答：考察全等证明，等腰直角三角形性质。

△BD F≌△ADC∴DF=DC=4求线段长度：①全等证明②相似③勾股定理2．CD是Rt△ABC斜边AB上的高，将△BCD沿CD折叠，点B恰好落在AB的中点E处，则∠A等于（B）A. 25ºB.30ºC. 45ºD. 60º解答：考察直角三角形性质，若直角边等于斜边的一半，则该直角边对应的顶角为30º角。

或者用方程思想，归入一个三角形，180º求解。

3．如图，∠AOB=90°，∠B=30°，△A′OB′可以看作是由△AOB绕点O顺时针旋转α角度得到的，若点A′在AB上，则旋转角α的大小可以是（C）A. 30ºB.45ºC. 60ºD. 90º解答：'OA OA=∠A＝'OA A∠=60º，∴'AOA∠=60º所以旋转角为60º4．不等式1+x<0的解集在数轴上表示正确的是（）关键：抓住方向和分界点5．下列图形中，既是轴对称图形又是中心对称图形的是（C）6．如图，已知△OAB是等边三角形，OC⊥OB，OC=OB，将△OAB绕点O按逆时针方向旋转，使得OA与OC重合，得到△OCD，则旋转的角度是（A ）A. 150ºB. 120ºC. 90ºD. 60º关键：理解旋转角的定义。

7．如果kb>0，且不等式kx+b>0的解集是bxk<-，那么y=kx+b的图象可能是下列中的（C ）由不等式解集知k<0，而kb>0，所以b<0所以一次函数过二四象限，且与y轴交点在x轴下面。