2练习与答案概念解析

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新概念英语第二册82课课后习题详细答案

新概念英语第二册课后习题答案详解Lesson 82练习答案Key to written exercises1．难点练习答案1 wash up2 laugh at3 washed4 laughed5 wash2．多项选择题答案1. a根据课文第3-4行…these ‘monsters’…are simply strange fish, 可以推测只有 a. are probably unusual fish (或许是不寻常的鱼)与课文的内容相符，而其他3个选择都与课文所描述的情形不符。

2. b根据课文第6行…a peculiar fish was caught nea r Madagascar (在马达加斯加福建的海里捕到了一条奇怪的鱼)可以判断，只有b. an unusual fish 与课文中的内容一致，而其他3个选择都与课文的内容不符，所以选b.3. a该句的谓语动词claim(声称)是及物动词，它后面可以跟名词或以that 引导的从句，也可以跟to 加动词不定式做宾语。

只有a. that they have seen 是个从句，可以做claim 的宾语。

而其他3个选择都不正确。

b. have seen 既不是从句，又不是不定式，因为前面没有to,因此不能用在claim 后面；c. to be seen 虽然是不定式，但不定式的被动式不符合这个句子的要求；d. to being seen 不符合语法，所以选a.4. d本句中的关系从句应该是被动语态才合乎语法，才能使句子意思完整。

a. which, b. which have 不合乎语法；c. which have being 也不合乎语法，只有选d. which have been 能构成被动语态关系从句，意思完整。

5. ca. realizing ,b. having realized 都不合乎语法，因为他们都不能直接跟在when 后面，when 是连词，它后面应该跟从句。

新概念英语2同步读写练习册-参考答案

Lesson 3 阅读理解（1）答案与解析 1. C。a story about an English sailor 已说明这个水手为英国人。 2. D。在第一段第二行至第三行写到，一天他把茶叶作为礼物给妈妈带了回来。bought some tea as a
present。 3. A。选择正确的一项。通读第一段，在段尾应注意到 nobody liked the tea leaves 证明没案与解析 1. B。our classroom faces our school garden 译为教室面对着花园，即花园也面对着教室。 2. D。首先读清题，让选择不正确的一项。故把 A、B、C、D 带回原文中去，在第一段第四行写到
在游泳池周围是各种各样的鲜花，故 A 正确，在第三行提到 B 为正确，同样在第三行写到 C 也
2
4. D。适用于排除法。A 不是新袜子，文章中没有说；B 读完后我们知道实际上并没有洞，故 B 不对；C 他这双袜子还没穿多长时间，文中没提。
英汉翻译 1. “I might as well have them!” I said sadly. 2. Word has it he’s married. 3. Word your idea clearly. 4. Words cut more than swords. 5. I hope you will come back whole. 6. Nature is a whole. 7. The whole of one week was spent on the beach. 8. The new auditorium can hold 4,000 people.
percent. 5. After having spent whole mornings on the river,I always go home with an empty bag. 6. I have been offered a large sum of money to go away,but I am determined to stay here. 7. Last year when we were travelling across the Channel,Jane put a piece of paper with her name and

词项逻辑章节练习- 答案与解析

词项逻辑练习答案与解析1.0概念与定义1.1概念答案与解析1．[解题分析]正确答案：C。

西蒙的结论：机器不思考，通过计算机执行复杂操作，但是缺乏人类灵活性，把机器指代为计算机。

而罗伯特的结论：机器思考，人类就是机器，把机器指代为人类。

可见，“机器”一词在两人的对话中有不同的理解。

所以C项为正确答案。

2．[解题分析]正确答案：C。

题干中两次出现“维生素缺乏”，参照对象不同。

对于一个词语或一个概念，不能够指代两种意思或者出现两种参照对象。

第一次说，许多怀孕妇女经常遭受维生素缺乏，指的是怀孕妇女与正常人比，参考对象是正常人。

常人也许需要100克/天，怀孕妇女也许需要150克/天。

第二次说，这通常不是由于她们饮食中的维生素缺乏，指的是她们吃的食品tp的维生素缺乏，饮食代表某些食物和饮料。

因此参照对象是正常食品。

正常食品中也许100克包含10克维生素，但是她们吃的食品中，也许100克只包含5克维生素。

因此，C项为正确答案。

3．[解题分析]正确答案：B。

题干所反驳的观点的结论是：到21世纪，和发达国家相比，发展中国家将有更多的人死于艾滋病。

其根据是：艾滋病毒感染者人数在发达国家趋于稳定或略有下降，在发展中国家却持续快速上升。

题干对此所作的反驳实际上指出：上述观点把“死于艾滋病的人数”和“感染艾滋病毒的人数”这两个相近的概念错误地当作同一概念使用；艾滋病毒感染者人数在发达国家虽低于发展中国家，但由于发达国家的艾滋病感染者从感染到发病，以及从发病到死亡的平均时间要大大短于发展中国家，因此，其实际死于艾滋病的人数仍可能多于发展中国家。

因此，B项恰当地概括了题干中的反驳所使用的方法。

其余各项均不恰当。

4．[解题分析]正确答案：B。

如图1--1--1，从地域情况看：由于介绍中涉及了这寝室中所有的人，“一个是大连人，两个是北方人”，关键是大连人与北方人必有重合，也就还是两个人。

再加上“一个是云南人”，因此，是3个人。

图1--1--1从选课的情况看：虽然“三个人这学期选修了古典音乐欣赏”时没有用“只”字。

2020年《中级会计实务》第二章章节练习与答案解析

2020年《中级会计实务》第二章章节练习与答案解析第二章存货一、单项选择题1.A公司为制造企业，其在日常经营活动中发生的下列支出，不应计入存货成本的是（）。

A.生产车间的水电费等B.季节性停工损失C.产成品入库后的保管费D.小规模纳税人的增值税进项税额2.2×12年12月31日，A公司库存钢板乙（均用于生产甲产品）的账面价值（即成本）为185万元，市价为180万元，假设不发生其他销售费用；钢板乙生产的甲产品的市场销售价格总额由380万元下降为310万元，但生产成本仍为305万元，将钢板乙加工成甲产品尚需投入其他材料120万元，预计销售费用及税金为7万元，则2×12年末钢板乙的可变现净值为（）万元。

A.303B.183C.185D.1803.下列各项中，应计入存货实际成本中的是（）。

A.入库后的挑选整理费B.入库后的合理损耗C.存货采购过程中因遭受意外灾害发生的净损失D.商品流通企业外购商品时发生的运输费、装卸费、保险费等4.下列各项中，不应计入自行生产存货的制造费用的是（）。

A.生产车间管理人员的薪酬B.生产工人的薪酬C.机物料消耗D.季节性的停工损失5.资产负债表日，当存货成本低于可变现净值时，存货按（）计量。

A.成本B.可变现净值C.公允价值D.现值6.某制造企业为增值税一般纳税人，从外地购入一批原材料，收到增值税专用发票上注明的售价为400000元，增值税税款为52000元，材料运输途中取得的运输业增值税专用发票注明运费为2000元，增值税额为180元，另发生装卸费1000元，途中保险费800元，均以银行存款支付。

所购原材料到达后验收发现短缺20%，其中合理损耗5%，另15%的短缺尚待查明原因。

该批材料的采购成本为（）元。

A.387583B.403800C.343383D.3432307.某投资者以一批甲材料为对价取得A公司200万股普通股，每股面值1元，双方协议约定该批甲材料的价值为600万元（假定该价值是公允的）。

计算机二级c语言经典练习题及解析答案

计算机二级c语言经典练习题及解析答案一、单选题1. C语言中的三大基本数据类型包括（ B ）A.整型、实型、逻辑型B.整型、实型、字符型C.整型、逻辑型、字符型D.整型、实型、逻辑型、数组型2. 在C语言中，以下合法的字符常量是（ c ）A. '\048'B. 'ab'C. '\43'D. "\0"3.设x 为 int 型变量,执行下列语句: x=10; x+=x-=x-x; 则x的值为 ( B )A. 15B. 20C. 25D. 304. 定义如下变量和数组: int i, x[3][3]={1,2,3,4,5,6,7,8,9};则下面语句for(i=0;i<3;i++) printf("%d",x[i][2-i]); 的输出结果是（ C ）A. 1 4 7B. 1 5 9C. 3 5 7D. 3 6 95.逗号表达式(a=3*5,a*4),a+15的值是( b )A.15B. 30C. 60D. 756. .以下程序的输出结果是（ c ）。

main( ){ int x=10,y=11;printf("%d，%d\n",x--,--y);}A. 11,11B. 10,11C. 10, 10D.11,107.若一个外部变量的定义形式为static int x ; 其中static的作用是( d )A.将变量存放在静态存储区，使x的值可以永久保留B.使变量x可以由系统自动初始化C.使x的值可以永久保留D.使x只能在本文件内引用8.有如下变量说明：int k=2;则下面的循环共执行多少（ d ）次while (k!=0) {printf("%d",k);k--;}A．无限多次 B.０次 C.１次 D. 2次9.设有变量说明：int a=7,b=8；那么语句:printf("%d,%d\n",(a+b,a),(b,a+b));的输出应该是（ a ）A. 7,15B. 8,15C. 15,7D.15,810.若已定义：int a[9], *p=a;并在以后的语句中未改变p的值，不能表示a[1]地址的表达式是（ b ）A. p+1B. a++C. a+1D. ++p11. C语言变量名中不能使用的字符是（ d ）A. 数字B. 字母C. 下划线D. 关键字12.以下变量定义中合法的是（ a ）A.short a=2.1e-1;B. double b=1+5e0.5;C. long do=0xffe ;D. float 3_end=1-e3;13.若有说明语句char ch1=′\x79′;则ch1( c )A.包含4个字符B.包含3个字符C. 包含2个字符D.包含1个字符14.C语言中的函数( b )A. 可以嵌套定义B.嵌套调用和递归调用均可C. 不可以嵌套调用D. 可以嵌套调用但不可以递归调用15. 设整形变量a=12；则执行完语句a+=a-=a*a后a的值为（ c ）A. 552B. 264C. -264D. 14416.设a=1,b=2,c=3,d=4,则表达式：a>b?a:c<d?a:d的结果是（ a ）A．1 B．2 C．3 D．417.若有说明语句：int b[][4]={ 3,1,2,5,7,6,4}; 则b数组的行数为（ b ）A. 3B. 2C.无确定值D. 118. 若有定义：char c［10］;从键盘输入“LiFang”，则正确的函数引用是( c )A. scanf(″%c″,&c［10］);B. gets(c);C. scanf(″%s″,&c);D. gets(c［10］);19. 两个基类型相同的指针变量之间，不能进行的运算是( c )A. <B. =C. +D.-20. 下面程序段执行结果是( b )int i=5,k; k=(++i)+(++i)+(i++); printf("%d,%d",k,i);A. 24，8B. 21，8C. 21，7D. 24，721．以下选项中属于C语言的数据类型是（ b ）。

教师资格证(科目二)笔试强化训练习题与答案

幼儿1.周一，小王老师埋怨说：“可可过完双休日,许多好习惯都没有了!”站在一旁的小张老师频频点头，说：“啊，家长不能按照我们的要求去做，还经常提一大堆意见，真拿这些家长没有办法。

”问题：试分析小王老师和小张老师的观点，并谈谈如何有效开展家园合作?答案材料中小王、小张老师的教育观点是欠妥的。

有效开展家园合作的方法如下：(1) 作为幼儿教师，应该尊重家长。

对家长提出的要求应切合实际，体谅家长的心情。

作为幼儿教师要帮助家长走出教育误区，让家长明确教育孩子的责任，明确家庭教育是终生的，更要明确幼儿期的教育对孩子的影响是最大的，实现有效地家园共育。

(2) 家长要积极配合，与幼儿园教育同步。

家长要密切、主动地配合班主任教师实施教育计划，正确要求和教导孩子，创造条件使家庭教育与幼儿园教育相互促进，巩固教育成果。

材料中孩子过了一个双休日，再回到幼儿园后，许多良好的行为习惯就退步了，幼儿园的教育成果就消失了，家长应该配合幼儿园的工作。

(3) 作为材料中的小王、小张两位老师应该主动和家长联系、沟通，让家长了解孩子在幼儿园的表现，针对孩子的优缺点，及时给予表扬或纠正，而不是一味地埋怨孩子和家长。

(4) 家长要积极参加幼儿园举办的各种家长开放日活动，重视家园联系手册，注意与班主任老师沟通，及时了解孩子在园的行为表现和各方面的发展，还可以满足孩子的心理需要。

2.下面家园合作的方法中，属于间接合作方式的是( )。

A.家园联系手册B.家长开放日活动C.家长老师制度D.开展亲子活动答案答案：A解析：本题考查学前教育机构与家庭合作共育的形式。

联系手册是记录幼儿在家庭和幼儿园活动情况的中介方式，通过联系手册，家长了解幼儿的在园情况，适用于与不宜见面的家长联系，属于间接合作。

B项，家长开放日属于直接合作方式。

C项，家长老师制度是家长参与进幼儿园教学中，属于直接方式。

D项，亲子活动属于直接方式。

故本题答案为A。

3.今天，小强又在洗手间里玩得“水漫金山”，并把一瓶洗手液全部挤进了洗手池。

《微观经济学》第2章需求与供给练习题及答案解析

第二章需求与供给一、选择题1.随着公共汽车车票的价格上升，会出现公共汽车车票的( )。

A. 需求量增加；B. 需求量减少；C. 需求增加；D. 需求减少解析：B.本题考察需求量的含义，商品本身价格的变化导致的需求数量的变化被称为需求量的变化。

表示在不同的价格下消费者改变了消费数量。

2.随着公共汽车票的价格大幅下降，会出现私人汽车的( )。

A. 需求量增加；B. 需求量减少；C. 需求增加；D. 需求减少解析：D.本题考察需求的含义，商品本身价格以外的因素发生变化也就是非价格因素的变化导致的需求数量的变化被称为需求的变化。

表示在每一个与以前相同的价格下消费者改变了消费数量。

公共汽车和私人汽车互为替代品，替代品价格下降，被研究对象的需求会跟着下降，消费者在相同的价格下减少了对私人汽车的需求数量。

3.随着汽油价格大幅下降，会出现私人汽车的( )。

A. 需求量增加；B. 需求量减少；C. 需求增加；D. 需求减少解析：C.本题考察需求的含义，商品本身价格以外的因素发生变化也就是非价格因素的变化导致的需求数量的变化被称为需求的变化。

表示在每一个与以前相同的价格下消费者改变了消费数量。

汽油和私人汽车互为互补品，互补品价格下降，被研究对象的需求数量会增加，消费者在相同的价格下增加了对私人汽车的需求数量。

4. 随着养猪专业户的增加，会出现生猪的( )。

A. 需求量增加；B. 需求量减少；C. 需求增加；D. 需求减少解析：A. 本题考察需求量的含义，商品本身价格的变化导致的需求数量的变化被称需求量的变化。

表示在不同的价格下消费者改变了消费数量。

本题供给增加导致生猪价格下降，在较低的价格下消费者增加了生猪的需求数量，是需求量的变化。

5.随着商品房价格上升，商品房的（）A.供给增加；B.供给量增加；C.供给减少；D.供给量减少。

解析：B.本题考察供给量的含义，商品本身价格的变化导致的供给数量的变化被称供给量的变化。

新概念英语第2册练习题详解-- L65-90(含答案)

Lesson 65(2)＆68(1)1、题干：The car stopped just in time to ____ a traffic accident.A. preventB. holdC. keepD. remove答案：A题型：选择题解析：句意：那个车及时的停了下来，阻止了一场交通事故。

prevent在句中是阻止的意思，符合题意。

hold是拿住，扣留；keep是保持；remove是去除，迁移。

B,C,D都不符合题意。

2、题干：I insist ____ your taking immediate action to put this right.A. inB. atC. onD. for答案：C题型：选择题解析：句意：我坚决要求你立即采取行动把事情处理好。

insist on doing sth.表示坚持做什么事。

介词用on，所以选C。

3、题干：Jean did not have time to go to the concert last night because she was busy ____ for her examination.A. to prepareB. to be preparedC. preparingD. being prepared答案：C题型：选择题解析：句意：简昨晚没有时间去音乐会，因为她在忙于准备她的考试。

这里不存在被动关系，所以B和D都排除。

be busy doing sth. 表示忙于做什么事，所以选C。

4、题干：____ hard he works, he cannot get a promotion.A. HowB. No matter howC. No matter whatD. No matter答案：B题型：选择题解析：句意：无论他怎么工作努力，他都不能得到竞升。

No matter常与how, when, where, what, who等引导的从句相连。

新概念英语第二册练习语法讲与练：十一、交际英语(含答案)

知识要点：一、Greeting（问候）1、Good morning! (afternoon, evening)2、Hello! (Hi)3、How do you do?4、How are you?5、How are you getting on with your studies?6、How's everything with you?7、Did you have a nice holiday? (summer vacation)二、Introduction（介绍）A．Introduction:1、This is my friend, Tom..2、Let me introuduce you to my friend, Tom.3、May I introduce myself? I'm Tom.4、Please allow me to introduce my friend, Tom.5、I'd like you to meet my friend Tom.B．Responses:1、How do you do? Pleased to meet you. (Glad to meet you. Nice to meet you.)2、It's my pleasure to have this chance to meet you.三、Farewells（告别）A．Farewells:1、It's getting late. I must be going.2、It's five o'clock already. I must be off now.3、Oh, God, it's late, I've got to go.4、It's time I was going, I'm afraid.5、I think I must go now.6、I think I'd better leave.7、I'm glad to have met you.1、Come again whenever you are free.2、If you pass my home, drop in.3、Good night, have a nice dream.4、Can't you stay a little longer?5、I hope we'll meet again sometime.四、Asking and Directing the Way（问路和指路）A．Asking the way:1、Can you tell me the way to the post office?2、Is this the way to the post office?3、Excuse me, how can I get to the post office?4、Which is the nearest way to the post office?5、Is the post office far from here?6、How long will it take me to get to the post office?7、Excuse me, is there a post office near here?8、Excuse me, does this bus go to the post office? B．Responses:1、Go ahead till you come to the next crossing.2、No, it's not far from here. It's only about ten minutes' walk.3、It's about 200 yards down the street.4、Take Bus No. 3 and it will take you right there.5、Go down the street and take the second turning on the left.五、Asking for Time and Date（询问时间与日期）A．Asking:1、What time is it now?2、What's the time by your watch?3、What day is it today?4、What is the date today?5、Is your watch correct?1、It's ten.2、It's Wednesday.3、It's October, 8th.4、My watch says it's 7:30.5、My watch always keeps good time.六、Asking about Health（询问健康）A．Asking:1、How are you these days?2、What's wrong with you?3、Have you seen the doctor?4、You look tired. What's wrong?B．Responses:1、I'm not quite myself today.2、My stomach hurts3、I don't feel like eating anything today.4、I've got a bad cold.七、Talking about Weather（谈论天气）1、It's a fine day, isn't it?2、What's the temperature today?3、What's the weather like today?4、How is the weather?5、What's the weather going to be like at the weekend?6、Do you like the weather in Beijing?7、Do you think that we are going to have snow today?八、Invitations（邀请）A．Invitations:1、Would you like to come to my birthday party?2、Will you be able to come to my birthday party?3、I'd be very glad if you would come to my birthday party.4、Can you fix a time for a picnic?5、Are you free tomorrow? What (How) about having a picnic?6、Won't you come with me?7、You will come to have dinner with me, won't you? B．Responses:1、I'd be glad to, thank you.2、It's very kind of you to invite me.3、I'd like to, but I'm too busy.4、Thank you for your kind invitation, I will.5、I'm afraid not. I will have to look after my sick mother.6、I'm sorry, I can't. Thank you very much.九、Making an Appointment（约会）A．Making an appointment:1、Are you free this afternoon?2、How about tomorrow evening?3、Shall we meet at 7:00 at the gate of the cinema?4、When will you be able to see us?5、What time can I call on you?6、Will you be at home next Sunday?7、Don't forget to come to my birthday party. B．Responses:1、Tomorrow evening will be all right.2、Yes, I'll be free then.3、No, I won't be free then, but I'll be free next Wednesday.十、Making a phone call（打电话）A．Making a call:1、Hello, is Mary in?2、Hello, is that Mary speaking?3、Can I have your telephone number, please?4、Hello, may I speak to Mary?5、Could you ask him to call me, please?6、Who is it, please?B．Responses:1、This is Mary speaking.2、Hold on please.3、Mary, you are wanted on the phone.4、Mary isn't here right now. Can I take a message for you? 十一、Shopping（购物）A．Shop assistant:1、What can I do for you?2、Can (May) I help you?3、How much do you want?4、What about this (these)?B．Customer:1、I'd like to have a look at the sweater.2、That's too expensive (dear), I'm afraid.3、That's fine. I'll take it.4、How much is it?十二、Seeing the Doctor（看病）A．Doctor:1、What's wrong (the matter) with you?2、How long have you been like this?3、Let me examine you.4、Take this medicine three times a day.5、Drink plenty of water and take a good rest.6、It's nothing serious. Take it easy.B．Patient:1、There's something wrong with my stomach.2、I've got a pain here.3、I feel terrible (sick).4、This place hurts.5、I don't feel like eating anything.十三、Requests and Offers（请求与提供帮助）A．Requests:1、Can (could) you do something for me?2、Will (would) you do something for me?3、May I have some ice—cream?4、Please do me a favor.5、Please don't open the window.6、Do (Would) you mind turning down the radio?7、I wonder if you could lend me some money. B．Offers:1、Can (Shall) I help you?2、What can I do for you?3、Is there anything (else) I can do for you?4、Would you like me to do this for you?5、Would you like some help?十四、Asking for Permission（请求允许）A．Ask for permission:1、May I park my car here?2、Can (Could) I smoke in this room?3、Do (Would) you mind if I smoke (smoked) here?4、I wonder if I could smoke here. B．Responses:1、Certainly. (sure, of course), go ahead2、Yes, please.3、All right (OK).4、I'm sorry, it's not allowed.5、I'm afraid not.十五、Advice and Suggestions（劝告和建议）1、You'd better go to see the doctor.2、You should do it at once.3、Why not go on a picnic next Sunday?4、What (How) about going there by boat?5、Have you considered going there by boat?6、Shall we take a walk after supper?7、I suggest you do more reading.8、I advise you to take more exercises.【专项训练】一、Greeting1、—Hello, Joan.—Kate. Glad to see you.A．Hi B．Hello C．Good morning D．How do you do2、—Hi, haven't seen you for ages! You look fine.—. You look well too.A．Great B．Thanks C．Oh, no D．Not at all3、—How are you! Jane?—A．How are you, Mary? B．Fine, thanks, and you? C．All is right. D．That's good.4、—How do you do?—.A．Very well, thank you. B．Why, yes. I'm fine. C．How do you do? D．What about you?5、—How's everything with you?—.A．Fine, thanks B．It's all right C．Thank very much D．I'm very well6、—How's your work going?—A．Not too well, I'm afraid B．Quite good. What about you?C．Fine, how are you, then? D．Well, thanks a lot.7、—Did you have a good summer holiday?—Yes, thanks. Kate?—She's OK, thanks.A．what's is B．How is C．What's wrong D．and8、—Glad to meet you again. How are you?—I'm just .（老样子）A．my old self B．old myself C．myself old D．as old myself9、—It's nice to see you in New York. How's your family?—. My wife asked me to say hello to you.A．It's very well B．They are fine C．That's all right D．They are good10、—How's the young man?—.A．He's twenty B．He's a doctor C．He's much better D．He's David11、—How on with your new job these days?—Not bad.A．do you get B．did you get C．are you getting D．have you getting12、—Hello, Kate! Fancy meeting you here! Working again, are you?—Yes, , if I want to pass the exams.A．I've got to B．no other way C．I must do D．I have on way13、In the evening you meet your foreign teacher walking towards the reataurant, you should say .A．Good evening. B．Good night. C．Hello. Have you had your supper? D．Hi! Going to dinner.二、Introduction1、—Hi, Tom, this is my friend John.—A．Nice to meet you. B．How are you? C．Hi, Tom, I'm John. D．Are you Tom?2、—Let me introduce myself. I'm Albert.—.A．With a pleasure B．It's my pleasure C．I'm very pleased D．Pleased to meet you3、When you are introduced to someone, you should sayA．I'm getting on well B．I love you very much C．Fine, thank you. D．How do you do?4、—Have you met my girl friend, Susan? Susan, this is Li.—A．Glad to meet you. B．Thank you. C．How are you? D．Welcome home.5、—Please allow me to introuduce Mr. Smith, director of the department.—（久仰大名）A．I haven't seen you before. B．Haven't we met before?C．I've heard so much about you. D．How do you do?6、If Mr. Baker is here, will please make to me?A．you, yourself know B．you, you know C．he, us know D．he, himself know7、Let's give him a .A．warm welcome B．warming welcome C．warmly welcome D．warm welcoming三、Farewells1、—It's five o'clock already, I must be going.—Well, come again you are free.A．if B．whenever C．when D．while2、—Oh, God, it's late. I've got to go.—. Hope to see them soon.A．Give your parents my greetings B．Remember me to your parentsC．Show my greetings to your parents D．Say hello to your parents3、—It's time I was going, I'm afraid.—.A．Good evening B．Good night C．Bey—bey D．All the best4、—Well, I'd better let you get on with your work.—.A．I've wasted a lot of your time B．Thank you for a lovely afternoonC．You must be tired D．I'm sorry to trouble you5、—I'm flying home on Sunday morning.—I wish you .A．a pleasant journey home B．a good trip C．good lucky D．a happy journey travel6、—I think I must go now. See you later.—.A．You can go B．See you later C．Bye—bye D．So long7、—I'm glad to have met you. Drop by sometime.—.A．Thank you B．Give me a call C．Thanks, I certainly will D．Take care8、—It's very kind of you to come and see me off.—.A．It's my pleasure B．much better C．Don't say it D．No problem9、—I'm going camping this weekend.—.A．Can you fish? B．Have a good time C．No, I'm too busy D．Don't give up now10、—I'll go to Beijing this weekend..A．You are lucky B．The best of luck C．Thank you D．Good—bye四、Asking and Directing the Way1、—Excuse me, can you tell me where the nearest bus stop is?—I'm sorry, I have no idea. I .A．don't know B．am a strager here C．am new D．just come2、—will it take me to walk there?—About ten minutes.A．How far B．How long C．How much D．What far3、—Excuse me, is there a cinema around here?—Yes, please go , then turn right the first crossing.A．before, on B．ahead, at C．along, of D．forward, to4、—Excuse me, officer. I can't find the subway entrance.—See those glass doors? Go in and you will see it on your right.A．Can you help me? B．Where is it?C．Show me the way? D．You are very helpful5、—Is your school far from here?—Not very far, .A．it is about ten minutes' walk B．it nees to walk ten minutesC．you need walking ten minutes D．it is about ten—minutes walk6、—Could you tell me where the train station is?—.A．It's over there B．It's on the third floor C．No, I know little D．Yes, it's there7、—Excuse me, is this Mr. Brown's office?—I'm sorry, but Mr. Brown works here.A．not now B．no more C．not still D．no longer8、—Excuse me, can you tell me the way to the Sleeping Beauty Castle?—Yes, .A．Go down this road B．Go ahead till you see the entranceC．It's not far from here D．You can walk there五、Asking for Time and Date1、—?—It's the third of May?A．What day is it B．What's the date C．What's the time D．What's the clock2、—?—I'm sorry, my watch has stopped.A．When is it B．How much is it C．What is the time D．What's the clock3、—Is your watch right?—I think so. I set it the radio this morning.A．to B．of C．by D．through4、—What day is it today?—.A．July 27 B．Saturday C．the 27 of July D．Women's Day5、—How long has this bookshop been in business?—1982.A．After B．In C．From D．Since6、—When are you off?—at 21:24.—I hope you will have a good flight.A．My bus leaves B．My plane takes of C．My train goes D．My coach goes7、—will the work be ready?—two months.A．How long, AfterB．How often, For C．How soon, In D．How much, During8、—Is your watch correct?—Yes, my watch .A．runs well B．keeps good time C．keeps right D．never stops六、Asking about Health1、—How's your brother these days?—He hasn't been to well.—What's the matter?A．It's bad. B．I'm sorry to here that. C．Very badly. D．Why?2、—I haven't seen Bob lately.—As a matter of fact, he is ill.A．Where is he? B．Why? C．How is he? D．What does he do?3、—You sound as if you've got a cold. .—.—Get a good rest.A．Yes, as if B．I've been over—working C．I don't think so D．I hope not4、—I'm afraid I've got a bad cold.—.A．Never mind B．Keep away from meC．Better go and see a doctor D．You need to take medicine5、—John has caught a bad cold.—.A．It's too bad B．I don't believe it C．I'm sorry to hear that D．Take it easy6、—, Wang?—I've got a headache and I feel chilly.A．What's wrong B．What the matter is C．What is matter D．How about you7、—My stomach hurts. I feel sick.—For safety's sake, .A．go to see a doctor tomorrow B．Better to go to hospitalC．you'd better see a doctor at once D．Quick go to hospital七、Talking about Weather1、—It seems to be clearing up.—That will be a nice change, ?A．isn't it B．won't it C．can't it D．doesn't it2、—How cold is it today?—.A．Just so—so B．not too C．It's ten below zero D．Yes, it is3、—?—It's very cold and damp.A．What's the weather B．How's the weather todayC．Is it raining last night D．Might it have rained a lot4、—Do you like the weather in North China?—Not really, but now.A．I fit it B．I am used to it C．I used to it D．I agree to it5、—I wonder what the weather is going to be like tomorrow?—.—That's a good idea.A．Let's look through the paper B．Let's listen to the weather report on the radio C．Better be care of the radio D．Pay attention to the radio6、—.—It certainly is. The sun is shining and there is a pleasant breeze.—It's lovely.A．What nice it is B．How nice it is here C．It is like spring here D．What a good day here7、—What a nice day, isn't it?—A．You're right. B．Yes, isn't it? C．Yes, I agree. D．Really?8、—?—Yes, a bit cold, though.A．Cold weather, isn't it B．Bad weather, don't you thinkC．Freezing, isn't it D．Nice day, isn't it9、—today?—It's nice and warm.A．What's the weather B．What's the weather likeC．How is the weather like D．How does the weather look like10、—Do you think it is going to snow over the weekend?—.A．I don't believe B．I don't believe it C．I believe not so D．I believe not八、Invitations1、—Would you like to come around for a meal on my birthday?—Oh, yes. Thank you very much.A．When is your birthday? B．What day is your birthday?C．When were you born? D．What time is your birthday?2、—Have you got anything to do tomorrow?—.A．Yes, a lot of B．No, I won't be busy C．Certainly have D．Oh, that's a pity3、—Would you like to come to the cinema, Frank?—I have to do my homework.A．I don't, I'm afraid. B．I can't, I'm afraid. C．I'm sorry. D．Oh, pity!4、—Helen, I'd be glad if you would come and have tea with us on Friday.—.A．I try to go B．Many thanks for your kind invitation, I willC．I am very busy D．I must go5、—How about going to "Grand" for dinner?—. It's a long time since we had a good meal.A．wellB．That sounds like a good ideaC．Thank youD．But I'm too busy6、—Do you have to go? Can't you stay and have a meal?—I really think I must be off now.A．I'd love to, but B．Yes, I mustC．No, I don't have to but D．Yes, I can, but7、—Would you like to come to the party tomorrow?—.A．I'd like B．I like it C．I'd like to D．I'd like it8、—Will you be able to come and see us on Friday?—. I will have to work.A．I believe yes B．I don't hope so C．I won't be able to D．I'm afraid not9、—Shall I call for you of will you call for me?—You'd better come for me, ?A．can you B．OK C．really D．would you10、—Would you like to come to dinner tonight?—I'd like to, I'm too busy.A．and B．so C．as D．but九、Making an Appointment1、—Good morning, I'd like to see Mr. Baker, please.—Mr. Baker is quite busy. .A．You can't see him B．You won't be able to see him C．I'm afraid you won't be able to see him today. D．Please come next time.2、—Will you be able to come to see us sometime next month?—.A．I believe yes B．I don't hope so C．I won't be able to D．I'm afraid not3、—When will you be free this month, Mr. Smith?—, maybe we'll be free next Sunday.A．Let me be B．Let me see C．I'm afraid D．Think it over4、—What time can I call on you?—Any time this evening will be .A．OK B．right C．good D．free5、—I'm sorry to say that I can't come to your party tonight.—? Haven't we agreed on?A．What is it B．What is it now C．How is it D．What do you think6、—I have an appointment with Mr. Black. My name is John Brown.—Ah, yes, your appointment is at 4:15. , please, Mr. Brown?A．Wait a minute B．May you wait C．Can you wait a minute D．Take it easy7、—I'm sorry to keep you waiting.—Oh, not at all. I here only a few minutes.A．have been B．had been C．was D．will be8、—I'll come back tomorrow evening at nine. Can you meet me at the airport?—.A．All right B．All right. Nice to see you C．OK, wait for me D．All right. See you then9、—Will you be at home next Sunday?—A．Yes, but why? B．No, never mind. C．Not at all. D．Yes, of course not.10、—Don't forget to come to my birthday party tomorrow.—.A．I don't B．I won't C．I can't D．I haven't十、Making a phone call1、—Hello, is Henry in?—I'm sorry, he isn't here. ?A．What's the matter B．May I help you C．Is there anything D．Who are you2、—Could you ask him to call me, please?—! What's your name, please?A．S ure B．Oh C．Yes D．Well3、—?—Sure, it's 65250786.A．What's your telephone number B．Can I have your telephone numberC．Can I help you D．Can you make your telephone number4、The operator put him to 65250786.A．over B．on C．through D．in5、—Would you please tell John I called?—, please.A．Hold on B．Hold up C．Hold over D．Hold out6、—Is this number 61234567?—.A．No, you are wrong B．Sorry, you've got the wrong phoneC．No, you've dialed the wrong number D．No, you are right7、—Hello. May I speak to Zhou Lan?—Yes. .A．My name is Zhou Lan B．I'm Zhou Lan C．This is Zhou Lan speaking D．Zhou Lan's me8、—Do you want to have a message?—No, thanks. I in half an hour.A．will call again B．can call C．may phone him D．would call十一、Shopping1、—I'd like to buy a ten—speed bicycle.—How about this kind of type?—?A．How many is it B．How is it C．How much is it D．How expensive is2、—do you want?—Half a kilo, please.A．How many apples B．What are apples C．How many apple D．How much apples3、—What's the problem?—I'm afraid . It's a size 12 and it's too small.A．it don't suit B．it isn't fit C．it doesn't fit D．it isn't suit4、—How much is the blue skirt?—Ten dollars.A．How many size do you want? B．What size do you take?C．How large do you want? D．What size do you dress?5、—What about the dark blue sweater?—I like it, but it . You decide.A．costs too much B．take too much C．cost too many D．spends too much6、—Would you mind if I looked at some of your tape recorders?—.A．I'd better to see what the boss has to say about it B．Not at all, sir. Go right ahead C．Thank you for your coming D．Yes, do that, sir7、—Do you think the shirt really fits me?—. It goes well with your tie, too.A．Of course it does B．Yes, it does C．I am not sure D．Perhaps it does8、—Shall I ask the shop keeper if I can .—OK. And we'd better ask Mom whether it's cheap enough.A．take it on B．try it on C．wear D．put it on9、—How much did you the dress?—We 210 yuan for it.A．spend, pay for B．pay for, cost for C．pay for, paid D．take, pay十二、Seeing the Doctor1、—Well, ?—I feel hot and feverish.A．how do you feel like B．what's the matter with youC．what do you feel D．what illness do you have2、—?—Yes, I have. My temperature seems all right.A．Do you know your temperature B．Have you taken your temperatureC．Have you had your temperature D．Do you have your temperature3、—Oh, doctor. Are you sure it's nothing serious?—Yes, . I'm sure of that.A．he'll well soon B．he can be right quicklyC．he'll be all right soon D．he'll be good soon4、—You haven't had your lunch?—I had a little, but .A．I didn't feel like eating B．I didn't feel like to eatC．I didn't like to eating D．I didn't want to eating5、—?—I'm feeling even worse after taking the medicine.A．Are you feeling better B．How are you feelingC．How are you getting on D．How are you going6、—How about your headache now?—I can't get rid of it. I don't know what's the matter.—Take it easy. .—Thank you, doctor.A．Take this medicine before you go to bed B．Drink plenty of water and take a good restC．Take this medicine a day three times D．Go home and lie in bed for a good rest7、—My whole body feels weak and I've got a headache.—?A．How long ago did you get it this B．How long have you been like thisC．How soon have you got it D．How soon have you liked this十三、Requests and Offers1、—Can I count on you for help?—A．As you like. B．I'm sorry. C．Yes, you certainly can D．Why do you ask?2、—Could you spare me some ink?—.A．Yes, of course B．Not at all C．Yes, I cold D．Never mind3、—Let me help you carry the box.—No, I can manage, but .A．not at all B．it doesn't matter C．thank you just the same D．the same to you4、—Will you make me a kite?—.A．I'm glad B．I'll be glad C．I'm going to glad D．I'll be glad to5、—You seem to get lost. Need help?—A．Yes, would you help me with the bag? B．Yes, take me please.C．Help me find the key, please. D．I'm looking for Shanghai Road.6、—I'll be away on a business trip. Would you mind looking after my cat?—Not at all. .A．I've no time B．I'd rather not C．I'd like it D．I'd be happy to7、If you want to ask someone for help, which drills shouldn't you say ?A．Could you do me a favor B．Would you do me a favorC．May I ask a favor of you D．Can you give me a help8、—Can I have some meat?—Certainly, just .A．take it as you like B．eat it as you pleaseC．help yourself D．help yourself at home十四、Asking for Permission1、—Would you mind if I played the violin here?—.A．No, you won't B．No, do as you pleaseC．Yes, I don't mind D．Yes, do as you please2、—May I stop here?—No, you .A．mustn't B．might not C．needn't D．won't3、—Shall I tell John about it?—No, you . I've told him already.A．needn't B．wouldn't C．mustn't D．shouldn't4、—Can I use your tape recorder for a while?—Yes, .A．go ahead B．you can't broke it C．all right D．no, sorry5、? I didn't quite catch you.A．Will you please repeat it again B．PardonC．What did you say D．Say it again now6、Dick wants to go to the toilet during the class. He puts up his hand and says to his teacher:A．Excuse me, I can't stand any longer. B．Will you please let me go?C．Please, sir, may I be excused? D．I must go outside.7、—Can I go and have a look at it?—Yes, of course. .A．After me B．Come this way C．You may look D．This direction十五、Advice and Suggestions1、—I usually go there by train.—Why not by boat for a change?A．to try going B．trying to go C．to try and go D．try going2、—I'd like information about the management of your hotel.—Well, you could have word with the manager, he might be helpful A．some, a B．an, some C．some, some D．an, a3、—I'm afraid I've got a bad cold.—.A．Never mind B．Keep away from the medicineC．Better go and see a doctor D．You need take a medicine4、—I can't see the words on the blackboard.—Perhaps you need .A．to examine your eyes B．to have your eyes examined C．to have examined your eyes D．your eyes to be examined5、—Let's go and see our teacher on Teachers' Day.A．That's will do B．That's allC．That's all right D．All right【答案】一、Greetings:1、B2、B3、B4、C5、A6、B7、B8、A9、B 10、C11、C 12、A 13、A二、Introduction:1、A2、D3、D4、A5、C6、D7、A三、Farewells:1、B2、D3、B4、B5、A6、B7、C8、A9、B 10、B四、Asking and Directing the Way:1、B2、B3、B4、A5、A6、A7、D8、B五、Asking for Time and Date:1、B2、C3、C4、B5、D6、B7、C8、B六、Asking about Health:1、B2、C3、B4、C5、C6、A7、C七、Talking about Weather:1、B2、C3、B4、B5、B6、B7、B8、D9、B 10、D八、Invitation:1、B2、B3、B4、B5、B6、A7、C8、D9、B 10、D九、Making an Appointment:1、C2、D3、B4、A5、C6、C7、A8、D9、A 10、B十、Making a Phone Call:1、B2、A3、B4、C5、A6、C7、C8、A十一、Shopping:1、C2、A3、C4、B5、A6、B7、A8、B9、C十二、Seeing the Doctor:1、B2、B3、C4、A5、B6、A7、B十三、Requests and Offers:1、C2、A3、C4、D5、D6、D7、D8、C十四、Asking for Permission:1、B2、A3、A4、A5、B6、C7、B十五、Advice and Suggestions:1、D2、A3、C4、B5、D。

抽样检验的基本概念练习试卷2(题后含答案及解析)

抽样检验的基本概念练习试卷2(题后含答案及解析) 题型有：1. 单项选择题 2. 多项选择题 3. 综合分析题单项选择题每题1分。

每题的备选项中，只有1个符合题意。

1．在抽样检验中，不合格按质量特性的重要性或不符合的严重程度分类，可分为()。

A．A类、B类和C类B．A类和B类C．B类和C类D．A类正确答案：A解析：在抽样检验中，不合格是指单位产品的任何一个质量特性不满足规范要求。

通常按质量特性的重要性或不符合的严重程度将它们分为A、B、C三类：①A类不合格，是认为最被关注的一种不合格；②B类不合格，是认为关注程度比A类稍低的一种类型的不合格；③C类不合格，是关注程度低于A类和B类的一类不合格。

知识模块：抽样检验的基本概念2．在抽样检验中，被认为是最被关注的一种不合格是()。

A．A类不合格B．B类不合格C．C类不合格D．不合格正确答案：A 涉及知识点：抽样检验的基本概念3．有一个或一个以上不合格的()，称为不合格品。

A．产品B．单位产品C．个体D．样品正确答案：B 涉及知识点：抽样检验的基本概念4．有一个或一个以上B类不合格，也可能含有C类不合格，但不含有A类不合格的单位产品，称为()。

A．A类不合格品B．B类不合格品C．C类不合格品D．既可能是B类又可能是C类不合格品正确答案：B 涉及知识点：抽样检验的基本概念5．有三个C类不合格品，不含有A类和B类不合格品，则该单位产品是()。

A．A类不合格品B．B类不合格品C．C类不合格品D．既可能是B类又可能是C类不合格品正确答案：C 涉及知识点：抽样检验的基本概念6．某产品有5个质量特性，根据其重要程度不同分为A，B，C三类不合格，若对批量N =2000件进行全数检验，发现5个产品有不合格项，结果如表6.1-1所示。

则每百单位产品C类不合格数为()。

A．0.2B．0.3C．0.4D．0.8正确答案：C解析：知识模块：抽样检验的基本概念7．一批零件批量为N=10000件，已知其中包含的不合格品数为D=20件，则批中不合格品率为()。

2023年高考数学一轮复习第二章函数1函数的概念及其表示练习含解析

函数的概念及其表示考试要求 1.了解函数的含义，会求简单函数的定义域和值域.2.在实际情景中，会根据不同的需要选择恰当的方法(如图象法、列表法、解析法)表示函数.3.了解简单的分段函数，并会简单的应用．知识梳理 1．函数的概念一般地，设A ，B 是非空的实数集，如果对于集合A 中的任意一个数x ，按照某种确定的对应关系f ，在集合B 中都有唯一确定的数y 和它对应，那么就称f ：A →B 为从集合A 到集合B 的一个函数，记作y ＝f (x )，x ∈A . 2．函数的三要素(1)函数的三要素：定义域、对应关系、值域．(2)如果两个函数的定义域相同，并且对应关系完全一致，则这两个函数为同一个函数． 3．函数的表示法表示函数的常用方法有解析法、图象法和列表法． 4．分段函数若函数在其定义域的不同子集上，因对应关系不同而分别用几个不同的式子来表示，这种函数称为分段函数．常用结论1．直线x ＝a 与函数y ＝f (x )的图象至多有1个交点．2．在函数的定义中，非空数集A ，B ，A 即为函数的定义域，值域为B 的子集．3．分段函数虽由几个部分组成，但它表示的是一个函数．分段函数的定义域等于各段函数的定义域的并集，值域等于各段函数的值域的并集．思考辨析判断下列结论是否正确(请在括号中打“√”或“×”)(1)若两个函数的定义域和值域相同，则这两个函数是同一个函数．( × ) (2)函数y ＝f (x )的图象可以是一条封闭曲线．( × ) (3)y ＝x 0与y ＝1是同一个函数．( × ) (4)函数f (x )＝⎩⎪⎨⎪⎧x －1，x ≥0，x 2，x ＜0的定义域为R .( √ )教材改编题1．下列各曲线表示的y 与x 之间的关系中，y 不是x 的函数的是( )答案 C2．(多选)下列各组函数是同一个函数的是( ) A ．f (x )＝x 2－2x －1，g (s )＝s 2－2s －1B ．f (x )＝x －1，g (x )＝x 2－1x ＋1C ．f (x )＝x 2，g (x )＝⎩⎪⎨⎪⎧x ，x ≥0，－x ，x <0D ．f (x )＝－x 3，g (x )＝x －x 答案 AC3．(2022·长沙质检)已知函数f (x )＝⎩⎪⎨⎪⎧3x，x ≤0，log 3x ，x >0，则f ⎝ ⎛⎭⎪⎫f ⎝ ⎛⎭⎪⎫12等于( )A ．－1B ．2C.3D.12答案 D解析 ∵f ⎝ ⎛⎭⎪⎫12＝log 312<0， ∴f ⎝⎛⎭⎪⎫f⎝ ⎛⎭⎪⎫12＝31log 23＝12.题型一函数的定义域例1 (1)(2022·武汉模拟)函数f (x )＝1ln x ＋1＋4－x 2的定义域为( ) A ．[－2,0)∪(0,2]B ．(－1,0)∪(0,2]C ．[－2,2]D ．(－1,2]答案 B解析要使函数有意义，则需⎩⎪⎨⎪⎧x ＋1>0，x ＋1≠1，4－x 2≥0，解得－1<x ≤2且x ≠0，所以x ∈(－1,0)∪(0,2]．所以函数的定义域为(－1,0)∪(0,2]．(2)若函数f (x )的定义域为[0,2]，则函数f (x －1)的定义域为________．答案 [1,3]解析 ∵f (x )的定义域为[0,2]， ∴0≤x －1≤2，即1≤x ≤3， ∴函数f (x －1)的定义域为[1,3]．延伸探究将本例(2)改成“若函数f (x ＋1)的定义域为[0,2]”，则函数f (x －1)的定义域为________．答案 [2,4]解析 ∵f (x ＋1)的定义域为[0,2]， ∴0≤x ≤2， ∴1≤x ＋1≤3， ∴1≤x －1≤3， ∴2≤x ≤4，∴f (x －1)的定义域为[2,4]．教师备选1．(2022·西北师大附中月考)函数y ＝lg(x 2－4)＋x 2＋6x 的定义域是( ) A ．(－∞，－2)∪[0，＋∞) B ．(－∞，－6]∪(2，＋∞) C ．(－∞，－2]∪[0，＋∞) D ．(－∞，－6)∪[2，＋∞) 答案 B解析由题意，得⎩⎪⎨⎪⎧x 2－4>0，x 2＋6x ≥0，解得x >2或x ≤－6.因此函数的定义域为(－∞，－6]∪(2，＋∞)．2．已知函数f (x )＝x1－2x ，则函数f x －1x ＋1的定义域为( )A ．(－∞，1)B ．(－∞，－1)C ．(－∞，－1)∪(－1,0)D ．(－∞，－1)∪(－1,1) 答案 D解析令1－2x>0，即2x<1，即x <0.∴f (x )的定义域为(－∞，0)．∴函数f x －1x ＋1中，有⎩⎪⎨⎪⎧x －1<0，x ＋1≠0，解得x <1且x ≠－1.故函数f x －1x ＋1的定义域为(－∞，－1)∪(－1,1)．思维升华 (1)求给定函数的定义域：由函数解析式列出不等式(组)使解析式有意义． (2)求复合函数的定义域①若f (x )的定义域为[m ，n ]，则在f (g (x ))中，由m ≤g (x )≤n 解得x 的范围即为f (g (x ))的定义域．②若f (g (x ))的定义域为[m ，n ]，则由m ≤x ≤n 得到g (x )的范围，即为f (x )的定义域．跟踪训练1 (1)函数f (x )＝11－4x2＋ln(3x －1)的定义域为( )A.⎝ ⎛⎦⎥⎤13，12B.⎝ ⎛⎭⎪⎫13，12C.⎣⎢⎡⎭⎪⎫－12，14 D.⎣⎢⎡⎦⎥⎤－12，12 答案 B解析要使函数f (x )＝11－4x2＋ln(3x －1)有意义，则⎩⎪⎨⎪⎧1－4x 2>0，3x －1>0⇒13<x <12. ∴函数f (x )的定义域为⎝ ⎛⎭⎪⎫13，12. (2)已知函数f (x )的定义域为[－2,2]，则函数g (x )＝f (2x )＋1－2x的定义域为__________．答案 [－1,0]解析由条件可知，函数的定义域需满足⎩⎪⎨⎪⎧－2≤2x ≤2，1－2x≥0，解得－1≤x ≤0，所以函数g (x )的定义域是[－1,0]．题型二函数的解析式例2 (1)(2022·哈尔滨三中月考)已知f ⎝ ⎛⎭⎪⎫2x＋1＝lg x ，则f (x )的解析式为________．答案 f (x )＝lg2x －1(x >1) 解析令2x＋1＝t (t >1)，则x ＝2t －1，所以f (t )＝lg 2t －1(t >1)，所以f (x )＝lg2x －1(x >1)． (2)已知y ＝f (x )是二次函数，若方程f (x )＝0有两个相等实根，且f ′(x )＝2x ＋2，则f (x )＝________. 答案 x 2＋2x ＋1解析设f (x )＝ax 2＋bx ＋c (a ≠0)，则f ′(x )＝2ax ＋b ，∴2ax ＋b ＝2x ＋2，则a ＝1，b ＝2.∴f (x )＝x 2＋2x ＋c ，又f (x )＝0，即x 2＋2x ＋c ＝0有两个相等实根． ∴Δ＝4－4c ＝0，则c ＝1. 故f (x )＝x 2＋2x ＋1.(3)已知函数对任意的x 都有f (x )－2f (－x )＝2x ，则f (x )＝________. 答案 23x解析 ∵f (x )－2f (－x )＝2x ，① ∴f (－x )－2f (x )＝－2x ，② 由①②得f (x )＝23x .教师备选已知f (x )满足f (x )－2f ⎝ ⎛⎭⎪⎫1x ＝2x ，则f (x )＝________.答案－2x 3－43x解析 ∵f (x )－2f ⎝ ⎛⎭⎪⎫1x ＝2x ，①以1x代替①中的x ，得f ⎝ ⎛⎭⎪⎫1x －2f (x )＝2x，②①＋②×2得－3f (x )＝2x ＋4x，∴f (x )＝－2x 3－43x.思维升华函数解析式的求法(1)配凑法；(2)待定系数法；(3)换元法；(4)解方程组法．跟踪训练2 (1)已知f (1－sin x )＝cos 2x ，则f (x )＝________. 答案－x 2＋2x ，x ∈[0,2] 解析令t ＝1－sin x ， ∴t ∈[0,2]，sin x ＝1－t ，∴f (t )＝1－sin 2x ＝1－(1－t )2＝－t 2＋2t ，t ∈[0,2]， ∴f (x )＝－x 2＋2x ，x ∈[0,2]．(2)(2022·黄冈质检)已知f ⎝⎛⎭⎪⎫x 2＋1x2＝x 4＋1x4，则f (x )＝__________.答案 x 2－2，x ∈[2，＋∞)解析 ∵f ⎝⎛⎭⎪⎫x 2＋1x 2＝⎝⎛⎭⎪⎫x 2＋1x22－2，∴f (x )＝x 2－2，x ∈[2，＋∞)．题型三分段函数例3 (1)已知f (x )＝⎩⎪⎨⎪⎧cosπx ，x ≤1，f x －1＋1，x >1，则f ⎝ ⎛⎭⎪⎫43＋f⎝ ⎛⎭⎪⎫－43的值为( ) A.12B ．－12C ．－1D ．1 答案 D解析 f ⎝ ⎛⎭⎪⎫43＝f⎝ ⎛⎭⎪⎫43－1＋1＝f ⎝ ⎛⎭⎪⎫13＋1＝cosπ3＋1＝32，f ⎝ ⎛⎭⎪⎫－43＝cos ⎝ ⎛⎭⎪⎫－4π3＝cos2π3＝－12， ∴f ⎝ ⎛⎭⎪⎫43＋f ⎝ ⎛⎭⎪⎫－43＝32－12＝1.(2)已知f (x )＝⎩⎪⎨⎪⎧2x＋3，x >0，x 2－4，x ≤0，若f (a )＝5，则实数a 的值是__________；若f (f (a ))≤5，则实数a 的取值范围是__________．答案 1或－3 [－5，－1]解析 ①当a >0时，2a＋3＝5，解得a ＝1；当a ≤0时，a 2－4＝5，解得a ＝－3或a ＝3(舍)．综上，a ＝1或－3.②设t ＝f (a )，由f (t )≤5得－3≤t ≤1. 由－3≤f (a )≤1，解得－5≤a ≤－1. 教师备选1．已知函数f (x )＝⎩⎪⎨⎪⎧sin ⎝ ⎛⎭⎪⎫πx ＋π6，x >1，⎝ ⎛⎭⎪⎫12x，x <1，则f (f (2022))等于( )A ．－32B.22C.32D. 2 答案 B解析 f (2022)＝sin ⎝ ⎛⎭⎪⎫2022π＋π6＝sin π6＝12，∴f (f (2022))＝f ⎝ ⎛⎭⎪⎫12＝1212⎛⎫ ⎪⎝⎭＝22. 2．(2022·百校联盟联考)已知函数f (x )＝⎩⎪⎨⎪⎧x 3，x ≥0，－x 2，x <0，若对于任意的x ∈R ，|f (x )|≥ax ，则a ＝________. 答案 0解析当x ≥0时，|f (x )|＝x 3≥ax ，即x (x 2－a )≥0恒成立，则有a ≤0；当x <0时，|f (x )|＝x 2≥ax ，即a ≥x 恒成立，则有a ≥0，所以a ＝0.思维升华分段函数求值问题的解题思路(1)求函数值：当出现f (f (a ))的形式时，应从内到外依次求值．(2)求自变量的值：先假设所求的值在分段函数定义区间的各段上，然后求出相应自变量的值，切记要代入检验．跟踪训练3 (1)(2022·河北冀州一中模拟)设f (x )＝⎩⎪⎨⎪⎧x ＋2x－3，x ≥1，x 2＋1，x <1.则f (f (－1))＝________，f (x )的最小值是________．答案 0 22－3 解析 ∵f (－1)＝2，∴f (f (－1))＝f (2)＝2＋22－3＝0，当x ≥1时，f (x )＝x ＋2x－3≥22－3，当且仅当x ＝2时取等号，f (x )min ＝22－3，当x <1时，f (x )＝x 2＋1≥1，x ＝0时取等号， ∴f (x )min ＝1，综上有f (x )的最小值为22－3.(2)(2022·重庆质检)已知函数f (x )＝⎩⎪⎨⎪⎧log 2x ，x >1，x 2－1，x ≤1，则f (x )<f (x ＋1)的解集为________．答案 ⎝ ⎛⎭⎪⎫－12，＋∞解析当x ≤0时，x ＋1≤1，f (x )<f (x ＋1)，等价于x 2－1<(x ＋1)2－1，解得－12<x ≤0；当0<x ≤1时，x ＋1>1，此时f (x )＝x 2－1≤0，f (x ＋1)＝log 2(x ＋1)>0，∴当0<x ≤1时，恒有f (x )<f (x ＋1)；当x >1时，f (x )<f (x ＋1)⇔log 2x <log 2(x ＋1)恒成立．综上知，不等式f (x )<f (x ＋1)的解集为⎝ ⎛⎭⎪⎫－12，＋∞.课时精练1．(2022·重庆模拟)函数f (x )＝3－xlg x的定义域是( ) A ．(0,3) B ．(0,1)∪(1,3) C ．(0,3] D ．(0,1)∪(1,3]答案 D解析 ∵f (x )＝3－xlg x，∴⎩⎪⎨⎪⎧3－x ≥0，lg x ≠0，x >0，解得0<x <1或1<x ≤3，故函数的定义域为(0,1)∪(1,3]．2．若函数y ＝f (x )的定义域为M ＝{x |－2≤x ≤2}，值域为N ＝{y |0≤y ≤2}，则函数y ＝f (x )的图象可能是( )答案 B解析 A 中函数定义域不是[－2,2]；C 中图象不表示函数；D 中函数值域不是[0,2]． 3．(2022·安徽江淮十校联考)设函数f (x )＝⎩⎪⎨⎪⎧4x －12，x <1，a x ，x ≥1，若f ⎝ ⎛⎭⎪⎫f ⎝ ⎛⎭⎪⎫78＝8，则a 等于( ) A.12 B.34 C ．1 D ．2答案 D解析 f ⎝ ⎛⎭⎪⎫78＝4×78－12＝3，则f ⎝ ⎛⎭⎪⎫f ⎝ ⎛⎭⎪⎫78＝f (3)＝a 3，得a 3＝8，解得a ＝2.4．设函数f ⎝ ⎛⎭⎪⎫1－x 1＋x ＝x ，则f (x )的表达式为( )A.1＋x1－x(x ≠－1) B.1＋xx －1(x ≠－1) C.1－x1＋x(x ≠－1) D.2xx ＋1(x ≠－1) 答案 C解析令t ＝1－x 1＋x ，则x ＝1－t1＋t ，∴f (t )＝1－t 1＋t ，即f (x )＝1－x1＋x(x ≠－1)．5．如图，点P 在边长为1的正方形的边上运动，M 是CD 的中点，当P 沿A －B －C －M 运动时，设点P 经过的路程为x ，△APM 的面积为y ，则函数y ＝f (x )的图象大致是( )答案 A解析由题意可得y ＝f (x )＝⎩⎪⎨⎪⎧12x ，0≤x ＜1，34－x4，1≤x ＜2，54－12x ，2≤x ≤52.画出函数f (x )的大致图象，故选A.6．(多选)下列函数中，与y ＝x 是同一个函数的是( ) A ．y ＝3x 3B ．y ＝x 2C ．y ＝lg10xD ．y ＝10lg x答案 AC解析 y ＝x 的定义域为x ∈R ，值域为y ∈R ，对于A 选项，函数y ＝3x 3＝x 的定义域为x ∈R ，故是同一函数；对于B 选项，函数y ＝x 2＝||x ≥0，与y ＝x 的解析式、值域均不同，故不是同一函数；对于C 选项，函数y ＝lg10x＝x ，且定义域为R ，故是同一函数；对于D 选项，y ＝10lg x＝x 的定义域为(0，＋∞)，与函数y ＝x 的定义域不相同，故不是同一函数．7．(多选)(2022·张家界质检)设函数f (x )＝⎩⎪⎨⎪⎧1－x ，x ≤a ，2x，x >a ，若f (1)＝2f (0)，则实数a可以为( ) A ．－1B ．0C ．1D ．2 答案 AB 解析若a <0，则f (0)＝1，f (1)＝2，f (1)＝2f (0)成立；若0≤a <1，则f (0)＝1，f (1)＝2，f (1)＝2f (0)成立；若a ≥1，则f (0)＝1，f (1)＝0，f (1)＝2f (0)不成立．综上所述，实数a 的取值范围是(－∞，1)．8．(多选)具有性质：f ⎝ ⎛⎭⎪⎫1x ＝－f (x )的函数，我们称为满足“倒负”变换的函数，下列函数满足“倒负”变换的函数的是( ) A ．f (x )＝x －1xB ．f (x )＝ln1－x1＋xC ．f (x )＝1ex x-D ．f (x )＝⎩⎪⎨⎪⎧x ，0<x <1，0，x ＝1，－1x ，x >1答案 AD解析对于A ，f (x )＝x －1x，f ⎝ ⎛⎭⎪⎫1x ＝1x－x ＝－f (x )，满足题意；对于B ，f (x )＝ln1－x1＋x，则f ⎝ ⎛⎭⎪⎫1x ＝ln x －1x ＋1≠－f (x )，不满足；对于C ，f ⎝ ⎛⎭⎪⎫1x ＝111e xx -＝ex －1，－f (x )＝1ex x--≠f ⎝ ⎛⎭⎪⎫1x ，不满足；对于D ，f ⎝ ⎛⎭⎪⎫1x ＝⎩⎪⎨⎪⎧1x ，0<1x <1，0，1x ＝1，－x ，1x >1，即f ⎝ ⎛⎭⎪⎫1x ＝⎩⎪⎨⎪⎧1x ，x >1，0，x ＝1，－x ，0<x <1，则f ⎝ ⎛⎭⎪⎫1x ＝－f (x )满足“倒负”变换，故选AD.9．已知f (x 5)＝lg x ，则f (100)＝________. 答案 25解析令x 5＝100，则x ＝15100＝2510， ∴f (100)＝25lg 10＝25.10．函数f (x )＝ln(x －1)＋4＋3x －x 2的定义域为________．答案 (1,4]解析依题意⎩⎪⎨⎪⎧x －1>0，4＋3x －x 2≥0，解得1<x ≤4，∴f (x )的定义域为(1,4]．11．(2022·广州质检)已知函数f (x )＝⎩⎪⎨⎪⎧1－2a x ＋3a ，x <1，ln x ，x ≥1的值域为R ，则实数a的取值范围是________．答案 ⎣⎢⎡⎭⎪⎫－1，12 解析 ∵当x ≥1时，f (x )＝ln x ≥ln1＝0，又f (x )的值域为R ，故当x <1时，f (x )的值域包含(－∞，0)．故⎩⎪⎨⎪⎧1－2a >0，1－2a ＋3a ≥0，解得－1≤a <12.12．设函数f (x )＝⎩⎪⎨⎪⎧x ，x <0，1，x >0，则不等式xf (x )＋x ≤2的解集是________．答案 [－2,0)∪(0,1] 解析当x <0时，f (x )＝x ，代入xf (x )＋x ≤2得x 2＋x －2≤0，解得－2≤x <0；当x >0时，f (x )＝1，代入xf (x )＋x ≤2，解得0<x ≤1. 综上有－2≤x ＜0或0＜x ≤1.13．设函数f (x )＝⎩⎪⎨⎪⎧2－x，x ≤0，1，x >0，则满足f (x ＋1)<f (2x )的x 的取值范围是( ) A ．(－∞，－1] B ．(0，＋∞) C ．(－1,0) D ．(－∞，0)答案 D解析当x ≤0时，函数f (x )＝2－x是减函数，则f (x )≥f (0)＝1.作出f (x )的大致图象如图所示，结合图象知，要使f (x ＋1)＜f (2x )，当且仅当⎩⎪⎨⎪⎧x ＋1<0，2x <0，2x <x ＋1或⎩⎪⎨⎪⎧x ＋1≥0，2x <0，解得x <－1或－1≤x <0，即x <0.14．设函数f (x )＝⎩⎪⎨⎪⎧－x ＋λ，x <1λ∈R，2x，x ≥1，若对任意的a ∈R 都有f (f (a ))＝2f (a )成立，则λ的取值范围是______．答案 [2，＋∞) 解析当a ≥1时，2a≥2. ∴f (f (a ))＝f (2a)＝22a＝2f (a )恒成立．当a <1时，f (f (a ))＝f (－a ＋λ)＝2f (a )＝2λ－a ，∴λ－a ≥1，即λ≥a ＋1恒成立，由题意λ≥(a ＋1)max ，∴λ≥2，综上，λ的取值范围是[2，＋∞)．15．(多选)若函数f (x )满足：对定义域内任意的x 1，x 2(x 1≠x 2)，有f (x 1)＋f (x 2)>2f ⎝ ⎛⎭⎪⎫x 1＋x 22，则称函数f (x )具有H 性质．则下列函数中具有H 性质的是( )A ．f (x )＝⎝ ⎛⎭⎪⎫12xB ．f (x )＝ln xC ．f (x )＝x 2(x ≥0) D ．f (x )＝tan x ⎝ ⎛⎭⎪⎫0≤x <π2 答案 ACD解析若对定义域内任意的x 1，x 2(x 1≠x 2)，有f (x 1)＋f (x 2)>2f ⎝ ⎛⎭⎪⎫x 1＋x 22，则点(x 1，f (x 1))，(x 2，f (x 2))连线的中点在点⎝⎛⎭⎪⎫x 1＋x 22，f ⎝ ⎛⎭⎪⎫x 1＋x 22的上方，如图⎝⎛⎭⎪⎫其中a ＝f⎝ ⎛⎭⎪⎫x 1＋x 22，b ＝f x 1＋f x 22.根据函数f (x )＝⎝ ⎛⎭⎪⎫12x ，f (x )＝ln x ，f (x )＝x 2(x ≥0)，f (x )＝tan x ⎝⎛⎭⎪⎫0≤x <π2的图象可知，函数f (x )＝⎝ ⎛⎭⎪⎫12x ，f (x )＝x 2(x ≥0)，f (x )＝tan x ⎝⎛⎭⎪⎫0≤x <π2具有H 性质，函数f (x )＝ln x 不具有H 性质．16．设f (x )是定义在R 上的函数，且f (x ＋2)＝2f (x )，f (x )＝⎩⎪⎨⎪⎧2x ＋a ，－1<x <0，b e 2x，0≤x ≤1，其中a ，b 为正实数，e 为自然对数的底数，若f ⎝ ⎛⎭⎪⎫92＝f ⎝ ⎛⎭⎪⎫32，则a b 的取值范围为________．答案 (2e ，＋∞)解析因为f (x ＋2)＝2f (x )，所以f ⎝ ⎛⎭⎪⎫92＝f⎝ ⎛⎭⎪⎫12＋4＝(2)2f ⎝ ⎛⎭⎪⎫12＝2e b ，f ⎝ ⎛⎭⎪⎫32＝f ⎝ ⎛⎭⎪⎫－12＋2＝2f ⎝ ⎛⎭⎪⎫－12 ＝2⎣⎢⎡⎦⎥⎤2×⎝ ⎛⎭⎪⎫－12＋a ＝2(a －1)，因为f ⎝ ⎛⎭⎪⎫92＝f ⎝ ⎛⎭⎪⎫32，所以2(a －1)＝2e b ，所以a ＝2e b ＋1，因为b 为正实数，所以a b＝2e b ＋1b＝2e ＋1b∈(2e ，＋∞)，故a b的取值范围为(2e ，＋∞)．。

新概念第二册一课一练答案

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答案解析方法：答案解析方法部分介绍了如何通过上下文推断答案、如何理解句子结构等方法，有助于学习者提高语言运用能力。
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针对不同题型，总结解题技巧和思路针对错题，分析原因并加强练习定期复习答案总结，巩固所学知识与同学讨论答案，互相学习，共同进步
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针对不同学习阶段的学生，提供不同的练习难度和内容，以满足不同层次的需求。
注重培养学生的自主学习能力和思维能力，通过多样化的练习形式，引导学生主动思考和解决问题。
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结合教材中的知识点和实际应用场景，设计更具实用性和趣味性的练习题目，提高学生的兴趣和参与度。
在答案部分提供详细的解析和解题思路，帮助学生更好地理解题目和知识点，同时也可以作为教师备课的参考资料。
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结合课文内容，先做练习再对答案
对于不懂的题目，可以参考答案解析
不要抄袭答案，要独立思考完成练习
及时总结错题，查漏补缺
使用建议四
结合课文内容，先做练习，再核对答案
对于错误和不确定的答案，要深入理解并查找原因
总结易错知识点，加强记忆和理解
鼓励自主学习，不要依赖答案，积极思考和探索
感谢观看
汇报人：XX
答案总结
答案详尽：提供完整的答案解析，帮助学生理解题目
解析透彻：对答案进行详细的解析，帮助学生理解解题思路
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新概念英语第二册75课课后习题详细答案

新概念英语第二册课后习题答案详解Lesson 75练习答案Key to written exercises1．关键句型练习答案flew (1.1); crashed (1.2); was killed (1.2); grew dark (1.5); turned (1.6); put(1.6); could find (1.7); got (1.8); kept(1.8); could(1.8); tried to get(1.9); heard (1.9); wondered (1.10); could send (1.10); had(1.10); stamped out(1.11); saw(1.11); sent(1.11); arrived (1.12)(Note: Other past tenses <e.g. lay,[1.4]; knew[1.5];was [1.12]>are descriptive, i.e. they do not indicate something that happened.)2．难点练习答案1 grew/got/turned2 fell3 grew4 turn/go5 come/become6 grew7 growing/getting…growing/get ting8 got/grown9 fell10 come3．多项选择题答案1. c根据课文第1-2行可以推断，只有 c. it wasn’t flying in the right direction 才是飞机坠毁的原因，所以只有c. 是正确答案。

其他3个选择都不能说明飞机坠毁的原因。

2. a根据课文第11行a pilot saw the signal and sent a message 可以推测，只有a 是课文所暗示的内容，其他3个选择都与课文的内容不符。

3. b只有选 b. young 才能使该句同前一句意思相同.若选a. a youth 同前一句意思不符;c. a young 不合乎语法; d. youth 既不符合语法也不合乎题目意思.4. d此句是一般过去时疑问句。

新概念英语第二册课后练习题答案详解(第64课)

新概念英语第二册课后练习题答案详解(第64课)新概念英语第二册课后习题Lesson 641. c根据课文第6-9行，In 1860, a better plan was put forward by an Englishman...This would solve the problem of ventilation...能够判断只有c. his tunnel would be better ventilated(他的隧道会通风更好)是课文所暗示的情况，因为它说明了为什么William 的计划比Aime Thome de Gamond 的好的原因，其他3个选择都于课文实际内容不符合。

2. c根据课文第9-10行 Forty-two years later a tunnel was actually begun 能够看出，只有c. began a long time after William Low put up his plan 与课文事实相符，其他3个选择都与课文实际内容不符。

3. c前一句It would be possible to build a platform 意思为“建造一座平台是可能的”。

该句的主语是A platform, 需要选一个合适的动词做谓语，使它同前一句含义相同。

a. could build 和d. would build 都是主动语态，但是本句的主语是物不是人，故都不应该用主动语态。

b. would be built 和 c. could be built 都是被动语态，合乎语法，但是could be built (可能或能够被建成)比would be built (会被建成)意思更贴切，更接近前一句的含义，所以选c.4. c该句的谓语动词suggested 后面只能跟动名词短语或that 从句，从句中用should加动词原形才合乎语法。

所以只有c. building 是动名词，最符合语法，所以选c.a. b. d. 都不符合语法。

新概念英语同步练习册答案必备

新概念英语同步练习册答案必备新概念英语第一册练习册答案阅读理解(1) 答案与解析1. F。

由文中My name is Yang Hui...English teacher可知题干错误。

2. T。

由短文中的My name is Yang Hui. I’m your English teacher. 可知题干正确。

3. F。

文中对Tom Green只告诉大家他是一名新同学，并未告诉我们他是中国人，因而本题不正确。

这个题目有些同学可能从Tom Green的名字上推测他不是中国人，但是一定要注意，做题目时一定要从短文中找线索，不能想当然。

4. F。

短文的开头Yang Hui就说Good morning, class. 由此推断，这不是下午的课，而是上午的课。

5. F。

I’m fine. 中的I指代的是Yang Hui，如果弄清楚了指代关系，就能做对这道题目。

(2) 答案与解析1. 从老师问的Are you a new student及Li Dong的回答可以看出，他是一个学生。

要填student。

2. 从Li Dong见了Miss Hu能够准确地向她打招呼，说明他认识她。

该空应当填Hu。

3. 从Li Dong说的He’s my brother.能够得知，他是Li Ming的弟弟。

故应填写brother.4. Ling Dong说的I’m twelve.已经明确地告诉我们，他12岁了。

要填twelve。

5. 从Li Dong问三班就能看出，他是三班的学生。

应当填Three。

英汉翻译1. Is this your handbag2. Is this your pen3. Is this your pencil4. Excuse me, what time is it5. Sorry, I beg your parden.6. Is this your coat7. Is this your suit8. This is not my watch.新概念英语第一册Lesson123~124课后答案A1 She is the woman I drove to London.2 That s the film I saw.3 That s the man I spoke to.4 They are the thieves the police caught.5 These are the letters I typed.6 These are the people you asked me about.B1 Which man That man Yes, that s the man I saw yesterday.2 Which car That car Yes, that s the car I repaired yesterday.3 Which woman That woman Yes, that s the woman I drove to London yesterday.4 Which umbrella That umbrella Yes, that s the umbrella I bought yesterday.5 Which medicine That medicine Yes, that s the medicine I took yesterday.6 Which man That man Yes, that s the man I invited to my house yesterday.C1 That s right. This is the village I wrote to you about.2 That s right. He is the person I have heard about.3 That s right. This is the test I spoke to you about.4 That s right. She is the woman I read about.5 That s right. This is something(new) I haven t thought about.6 That s right. This is something I must decide about.新概念英语第一册Lesson 51课后练习册答案阅读理解(1)答案与解析1. A。

新概念英语第二册课后练习题答案详解（第51课）

新概念英语第二册课后练习题答案详解（第51课）新概念英语第二册课后练习题答案详解(第51课)新概念英语第二册课后习题Lesson 511. b根据课文第6-7行…and was not surprised to see that Hugh was still as fat as ever 能够看出只有b. but he didn’t lose any weight at all 与课文的实际内容相符，其他3个选择都与课文的实际情况相符。

2. c根据课文第9-10行he explained that his diet was sostrict that he had to reward himself occasionally 能够判断只有c. hasn’t kept to a strict diet(没有严格的控制饮食)是课文所暗示的情况，而其他3个选择都不符课文的实际内容。

3. d只有选d. is 才能使这个句子的意义和时态同前一句相协调. a. was 时态不对. b. has 不是系动词,不能跟形容词.c. has been 时态不对,表示"他现在仍然很胖",没有必要用现在完成时.4. d本句的时间状语是How long ago 表示过去的时间，所以应该用一般过去时。

a. will he begin 是将来时;b. has he begun 是完成时;c. was he beginning 是过去实行时，这3个选择时态都不对，只有d. did he begin 是一般过去时，最合乎语法，所以应该选d.5. d只有d. in 能够同本句的动词included 连用表示“包括”，所以d.是准确的。

其他3个都不能同 include 连用构成短语动词。

6. a这是一个一般过去时疑问句，需要选一个准确的谓语动词，只有a. hide 是原形动词，最符合语法，因为疑问句中已经有助动词did 了，所以谓语动词要用动词原形，而不能用过去式。

高中生物必修二DNA的复制练习题含答案

高中生物必修二DNA的复制练习题含答案学校：__________ 班级：__________ 姓名：__________ 考号：__________1. 如图为真核细胞DNA复制过程模式图，下列分析错误的是（）A.酶①能使DNA双链的配对碱基之间的氢键断开B.图中可体现出边解旋边复制及半保留复制的特点C.DNA复制的场所可发生在细胞核、线粒体和叶绿体处D.若一双链DNA分子在复制解旋时，一条链上某位点的一个T变成了C，则该DNA经n次复制后，发生差错的DNA占1/2n2. a个被放射性元素标记了双链DNA的噬菌体，侵染细菌后，细菌破裂释放出b个子噬菌体，其中具有放射性的噬菌体的比例为（）A.a/bB.a/（2b）C.2a/bD.2/b3. 下列关于人体细胞内DNA复制的叙述，错误的是（）A.主要在细胞核内复制B.复制以两条DNA母链为模板C.复制以4种核糖核苷酸为原料D.DNA复制会消耗能量4. 下列关于DNA复制的叙述，正确的是（）A.DNA分子在解旋酶的作用下，水解成脱氧核苷酸B.在全部解旋之后才开始碱基配对C.解旋后以一条母链为模板合成两条新的子链D.复制后，每个新DNA分子中含有一条母链和一条子链5. 下图为真核细胞DNA复制过程的模式图。

据图分析，下列相关叙述错误的是（）A.由图示可知，DNA分子复制的方式是半保留复制B.DNA解旋酶能使双链DNA解开，且需要消耗ATPC.图中引物与相应DNA片段结合遵循碱基互补配对原则D.DNA在复制过程中，先全部解旋，再复制6. 关于DNA分子复制的叙述，正确的是（）A.产物是脱氧核苷酸B.场所主要是线粒体C.原料是氨基酸D.边解旋边复制7. 下列关于DNA复制的叙述，正确的是（）A.细胞中表达出DNA解旋酶则说明细胞已经高度分化B.形成子链时，先形成氢键，后形成磷酸二酯键C.DNA复制不是沿着整条DNA长链进行的D.DNA复制保证了亲子代细胞遗传物质是相同的8. 将某植物（2N=4）的一个根尖细胞放在含3H标记的胸腺嘧啶脱氧核苷酸的培养基中完成一个细胞周期，然后将子代细胞转入不含放射性标记的培养基中继续培养一个细胞周期。