Grammer Homework2
人教版PEP八年级上册Unit2第二课时(SectionAGrammar Focus-3c)优秀课件
Section A Grammar Focus-3c
Warming up→ Grammar focus → Presentation→ Exercises→ Summary → Homework
人教版 英语 八年级上册
Learning goals
➢ Sometimes he goes to work by bus.
Grammar Focus
Find the questions and answers that ask about the frequency of the activity
What do you usually do on weekends? What do they do on weekends? What does she do on weekends? How often do you go to the movies? How often does he watch TV? Do you go shopping?
maybe
副词,常位于句首作状语,意为”大概;或许;可能”,相当于 perhaps。
may be
may是情态动词,may be为“情态动词+动词原形”结构,在 句中作谓语,意为“可能是”。
➢ Maybe she is a doctor. = She may be a doctor.
Grammar Focus
Mark the verbs in the right column
I always exercise. They often help with housework. She sometimes goes shopping. I go to the movies maybe once a month. He hardly ever watches TV. No, I never go shopping.
高考口语Part B翻译作业homework2
1. 你打算毕业之后做什么? 2. 你最喜欢什么样的文章呢? 3. 你在校时什么时候最想念父母? 4. 你觉得有必要加强师生间的课后对话吗? 5. 毕业典礼上我们应该邀请谁? 6. 你退休后经常自己做饭吗? 7. 你觉得谁是我们班上最高的同学? 8. 什么样的学生最容易得到老师的欣赏? 9. 你觉得合作对于学习很重要吗? 10. 作为学生,你了解成功的秘诀吗? 11.什么是你最难忘的经历? 12.你觉得退休后还需要继续学习吗?
What was James interested in when he was young? Who had the biggest effect/ influence on you? Who influenced you most? 2 Could you please speak a little more? What do you mean by “learning styles?” How did you learn a foreign language?
2. 你能说说英国人吗?
3. 你还有别的困难吗?
4Part B Role Play 情景介绍 角色:你是病人
任务:(1) 向医生咨询健康问题。
(2) 根据谈话内容回答问题。 1. 那我该做什么呢? 2. 我还需要注意什么吗?
3. 你觉得我需要吃药吗?
1
Does James like music as much as you?
(1)采访Dr Brown 有关外语学习的问题。
(2)根据谈话内容回答问题。 1. 你能再多说点吗? 2. 你说的学习风格是什么意思?
3. 你是如何学习外语的?
3Part B Role Play 情景介绍 角色:你是学生
语言学Homework 2
Homework TwoState whether each of the following statements is True or False. ( F ) 1. [i:] and [i] are allophones of the same phoneme.( T ) 2. Not all English phonemes have allophones.( F ) 3. The same set of vowels is used in all languages.( T ) 4. All syllables must contain at least one vowel.( F ) 5. The word people is monosyllabic.( F ) 6. English is a tone language.( F ) 7. [s] is a fricative in English but [h] is not.( T ) 8. [f] is a fricative in English.( T ) 9. Affricates involve more than one manners of articulation.( T ) 10. The phrase “has to” pronounced as [hæztə] is a case of assimilation. ( F ) 11. [j] is a palatal fricative.( F ) 12. A syllable may or may not have a nucleus.( T ) 13. Articulatory phonetics, acoustic phonetics and auditory phonetics study speech sounds.( T ) 14. Fricative is among the eleven places of articulation which are distinguished on the IPA chart.( T ) 15. The word “hour” contains a diphthong and a pure vowel.( F ) 16. The sound /p/ in the word “expensive” is pronounced as a voiceless consonant.( F ) 17. In a standardized English syllable, the onset, the nucleus and the coda, all the three parts are compulsory.( F ) 18. The voiced dental fricative is /z/.( T ) 19. In English, pill and bill form a minimal pair, and so does life and knife. ( T ) 20. When allophones are in complementary distribution, they never occur in the same context.。
homework2 翻译 笔译
E—C:From this motive目的, I began to think seriously of matrimony婚姻生活, and chose my wife as she did her wedding gown结婚礼服, not for a fine glossy surfaces but such qualities as would wear well. To do her justice, she was a good-natured notable著名的woman; and as for breeding教养, there were few country ladies who could show more. She could read any English book without much spelling, but for pickling腌制,酸洗, preserving保存, and cookery烹调, none could excel胜过her. She prided 以....自豪herself also upon being an excellent contriver 发明者in house- keeping; tho' I could never find that we grew richer with all her contrivances. However, we loved each other tenderly温柔的, and our fondness increased as we grew old. There was in fact nothing that could make us angry with the world or each other. We had an elegant幽雅的house, situated in a fine country, and a good neighbourhood. The year was spent in moral or rural amusements; in visiting our rich neighbours, and relieving such as were poor. We had no revolutions to fear, nor fatigues劳累to undergo; all our adventures were by the fire-side, and all our migrations from the blue bed to the brown.As we lived near the road, we often had the traveller or stranger visit us to taste our gooseberry 鹅莓wine, for which we had great reputation; and I profess声称with the veracity 诚实of an historian, that I never knew one of them find fault with it. Our cousins too, even to the fortiethremove, all remembered their affinity吸引力,亲密关系, without any help from the Herald's 使者office, and came very frequently to see us. Some of them did us no great honour by these claims of kindred家族; as we had the blind, the maimed残废的, and the halt踌躇,停止amongst the number. However, my wife always insisted that as they were the same flesh and blood, they should sit with us at the same table. So that if we had not, very rich, we generally had very happy friends about us; for this remark will hold good thro' life, that the poorer the guest, the better pleased he ever is with being treated: and as some men gaze注视with admiration at the colours of a tulip郁金香, or the wing of a butterfly, so I was by nature an admirer of happy human faces. However, when any one of our relations was found to be a person of very bad character, a troublesome guest, or one we desired to get rid of, upon his leaving my house, I ever took care to lend him a riding coat骑车外套, or a pair of boots, or sometimes an horse of small value, and I always had the satisfaction of finding he never came back to return them. By this the house was cleared of such as we did not like; but never was the family of Wakefield韦克费尔德known to turn the traveller or the poor dependent out of doors.。
九年级英语下册unit2全套教案
九年级英语下册unit2全套教案九年级英语下册unit2全套教案9B Unit 2 welunitI. Teaching objectives:To introduxt about having a roblp wwuma2. To talk about what a robot can dTo leaadvantagbII. Teaching procedure:: Warm-up: To raise students’get studg andalking about robots:① Have youblms?② What kind of robots do you know?③ Do you like robots? Why?④ What do youbots can du?⑤ Would you buy a robuture? Why?2: weluThe puaactivate student’s knowledgbots and generaAudadaword box aage 19. Make sure that all students understand the meaningases such as ‘do the laundry, explorer dangerous places’wn word2. Explaxt. Daniel is explaining to Amy what robots cado. Ask studlversaPagwAsk two studadversation andaurage studalk about if robots are harmful? Dividudgroups to discu① What do robots do harm to human beings?② Why do they do harm to human beings?Laleaain ideaLadad aaAudact ou: Useful exlaint: 不+可数名词“抱怨”;可数名词“抱怨的行动或话,投诉”lain:动词:complain to / about2. post:动词‘邮寄’:g for sb.III. Homework:Ruseful vocabulary and2. ComplxPreview reading(1)教学小结:学生基本能掌握对话,理解机器人能为人类做好多事。
【课件】unit2sectionAGrammar人教版(2024)七年级英语上册
(I) books.I read every day.
4.A: Whose caps are these? B: They're mygransparen(gtsr’andparents). They like wearing caps.
5.A: Whose schoolbag is this? B: It's Teng Fei’s(Teng Fei).He likes the colour blue.
pong every week.
sport.ຫໍສະໝຸດ They have some nice ping-pong bats.
Teng Fei's father has a fishing
rod.
Do you play the piano?
Yes,I do./No,I don't.
Does your father spend a lot of time fishing?Yes,he does./No,he doesn't.
Unit2 We’re Family! SectionAGrammar
·Language goals
In this unit, you will 1. talk about your family with the simple present tense (do). 2. identify ownership using -’s. 3. describe family members in a photo. 4. explore the meaning of being a family.
01 Key words
chess 国际象棋 chinese chess 中国象棋 funny 好笑的;奇怪的 laugh 笑;发笑 n.笑声 different 不同的 violin 小提琴 have fun 玩得高兴
ComputerHomework2计算机配置
最高规格CPU Intel酷睿i7 3960X ¥6850散热系统ZALMAN RESERA TOR XT ¥3999主板华硕Rampage III Black ¥4999内存海盗船DDR3 2000 6G套装¥5000机械硬盘西部数据2TB/64M/SA TA2/RE ¥1700固态硬盘金胜维PCI-E存储卡MC1S81M2T ¥75000显卡华硕MARS II/2DIS/3GD5 ¥14000声卡E-MU 1616M ¥3790光驱索尼VRDMC10 ¥2990显示器三棱56P-QF60LCU ¥598000 鼠标LG LSM-100 ¥1599键盘Cherry G80-2100 ¥2100机箱AX 刀锋战士至尊版¥9999电源金河田龙霸1500ELA ¥3368音响惠威H System ¥8880总价¥742274最低规格CPU AMD 闪龙3000+ AM2(散) ¥90散热器A VC扇魔师¥20内存金士顿1GB DDR2 800 ¥70硬盘日立160GB 7200转8MB(串口/散)¥260主板梅捷SY-AMN68S-RL ¥299显卡集成NVIDIA Geforce 7025 ¥270显示器EMC A71 ¥490光存储华硕DVD-E818A3 ¥110机箱/电源W103/世纪之星飙霸¥160键盘鼠标双巧星双巧手1+1套装¥40总价¥1809 个人规格CPU Intel 酷睿i3 4130(盒)¥849主板微星B85-G43 ¥649内存威刚4GB DDR3 1600(万紫千红)¥239硬盘希捷Barracuda 500GB 7200转16MB单碟¥320光驱先锋DVR-220CHV ¥139键盘鼠标罗技MK200键鼠套装¥89电源先马省电王400 ¥199机箱先马1号里程碑¥129显示器HKC S932i ¥509总价¥3122最高规格与个人规格最高配置的计算机运行速度快,反应灵敏,操作手感舒适,容量大可装载大型程序,无论是音质还是画面效果都是一流的,可满足游戏玩家的高要求。
《家庭作业》教案:掌握英语中不同学科作业的表达
我们来了解一下家庭作业在英语中的表达。
一般而言,我们可以使用homework这个词来表示家庭作业的概念,例如:1. I have a lot of homework to do.我有很多家庭作业要做。
2. My teacher assigned some homework over the weekend.我的老师布置了一些周末的家庭作业。
在不同学科下的作业也有不同的表达方式:1. 数学作业(Math homework)2. 英语作业(English homework)3. 历史作业(History homework)4. 地理作业(Geography homework)5. 科学作业(Science homework)6. 音乐作业(Music homework)7. 绘画作业(Art homework)8. 体育作业(Physical education/PE homework)了解了上面这些表达方式,我们就可以更加准确地传达我们需要完成的作业了。
我们来看看如何在课堂上教授这些表达方式:1. 数学作业(Math homework)在教授这个话题时,可以提供一些例句给学生们,例如:- I need to finish my math homework before dinner.我需要在晚餐前完成我的数学作业。
- Did you understand the math homework we were assigned today?你理解今天我们分配的数学作业了吗?- My math homework involves creating graphs and charts.我的数学作业涉及制作图表。
2. 英语作业(English homework)英语作业可能会涉及到写作文或读文章,在教授这个话题时,可以考虑一下以下例句:- My English homework is to write a 500-word essay on climate change.我的英语作业是写一篇500字的气候变化论文。
译林版高中英语必修一Unit2 Grammar and usage (II) 教案(雅礼)
7. I am on a diet. I find it hard to completely stay away from chocolate.Though/Although I am on a diet, I find it hard to completely stay away from chocolate.8.It turned out to be a lovely day. We decided to go out for a walk.It turned out to be a lovely day, so we decided to go out for a walk.【设计意图:通过复习让学生进一步掌握不同类型的复合句。
】Step 2 Applying the Rules.B1Below are some tips on how to use TeenHealthWeb. Join each pair of sentences to form a compound or complex sentence.1. Your password should be at least eight characters long. This makes it difficult to guess.Your password should be more than eight characters long because this makes it difficult to guess.2. Posts should not give out personal information. They should not include advertisements.Posts should not give out personal information and they should not include advertisements.3. Describe your problems clearly. Other people can understand them easily. Describe your problems clearly so other people can understand them easily.4. The experts will reply to you. They see your posts.The experts will reply to you when/once/as soon as they see your posts.5. What do you think of our forum? Let us know.Let us know what you think of our forum.。
在陪我写作业的英语
在陪我写作业的英语词汇学习1. 作业 - Homework2. 陪伴 - Accompany3. 帮助 - Help4. 困难 - Difficulty5. 理解 - Understand6. 练习 - Practice7. 语法 - Grammar8. 词汇 - Vocabulary9. 阅读 - Reading10. 写作 - Writing常用句型1. "Let's start with your homework."2. "What are you having trouble with?"3. "I can help you with your grammar."4. "Let's go over the vocabulary words."5. "Practice makes perfect."6. "Reading is a great way to improve your English."7. "Can you read this passage aloud?"8. "Let's work on your writing skills."9. "Do you understand the concept?"10. "Don't worry, we'll get through this together." 语法练习1. 现在进行时 - I am helping you with your homework.2. 一般现在时 - She does her homework every day.3. 一般过去时 - They did their homework last night.4. 将来时 - We will finish the homework by tomorrow.5. 现在完成时 - I have finished my homework.阅读理解Read the following passage and answer the questions:"Tom is a student who loves to read. He spends his evenings with a book in hand. His favorite genre is science fiction."1. What does Tom enjoy doing?2. What is Tom's favorite type of book?3. What time of day does Tom usually read?写作练习Write a short paragraph about your day. Include the following elements:- What time you woke up- What you did for homework- A new word you learned通过这些练习,你可以提高你的英语水平,无论是词汇、语法还是阅读和写作能力。
译林版高中英语选必一Unit2 Grammar and usage (II) 教案(雅礼版)
Unit 2 The universal languageGrammar and usage (II)Verb-ing forms as subjects and objects◆内容分析:本板块围绕单元话题,引导学生在有关“伯牙遇知音”的语篇中观察、探究动词-ing做主语和宾语的用法,并自主归纳其核心规则;再让学生通过句子、语篇两个层面练习巩固所学、内化新知;最后要求学生正确使用目标语法写出自己最喜欢的音乐及理由。
◆教学目标:By the end of this section, students will be able to:1.identify the use of verb-ing forms as subjects and objects;2.work out the rules of verb-ing used as subjects and objects;e the right forms of verb-ing to finish tasks of writing sentences and completingan article about his favorite music;4.apply verb-ing forms in new situations.◆教学重难点:1.To summarize the general rules;2.To apply the rules correctly and properly.动词-ing形式是动词的一种非谓语形式,包括现在分词和动名词两种。
动词-ing形式的时态和语态二、动词-ing形式作主语1.动词-ing形式直接作主语表示抽象的概念,通常直接置于句首,谓语动词用单数形式。
e.g.Reading aloud is a good way in learning a language.朗读是学习语言的一个好办法。
Getting up early is a good habit.早起是一种好习惯。
Homework 2
Homework 2: 英译汉、汉译英1.省译法1)We expect that the delivery will be effected at your earliest convenience.2)It’s a pleasure for us to offer you the goods as follows.3)To give you a general idea of the various kinds of cotton piece goods now available for export, we enclose a brochure and a price list.2.增译法1)Inflation was and still is the No. 1 problem of that country.2)Courage in excess becomes foolhardiness, affection weakness, thrift avarice.3.词性转换法1)企业组织可以选择在报纸或杂志上登广告,简要介绍所招聘职位的情况并征集应聘者的自荐信。
(动词翻译成名词)2)If major problems exist and goals are not being achieved, then changes need to be made in the company’s organizational or managerial structure. (名词翻译成动词)3)We are especially grateful to you for arranging the meeting for us with the Machinery Trading Delegation at such short notice. (形容词翻译成动词)4.被动语态1)The damage was covered by the insurance company.2)The Chinese trade delegation was given a hearty welcome.3)He preferred to be assigned something concerning trade to do.4)英文版学校简介运用形容词来代替名词。
2024-2025学年初中英语九年级上册(译林牛津版)教案Unit4Grammar
Unit 4 Growing upGrammar设计说明教学反思首先通过复习Reading,讨论关于Spud Webb的情况,来引入新课,呈现出相关的时间状语从句,通过一系列的讲解和练习,让学生掌握不同的连词的用法,学会各连词所引导的时间状语从句,并掌握与其相关的时态,学会用时间状语从句来表达自己的想法。
教学目标通过本课时的教学,让学生达成以下目标:1.知识目标(1)掌握单词:career, against。
(2)掌握连词before, after, when, while, since, till, until, as soon as 和whenever引导的时间状语从句。
2.能力目标(1)通过学习,掌握连词以及时间状语从句的用法。
(2)学会用时间状语从句来表达思想,培养写作能力。
3.情感目标通过谈论学生自身的变化让他们懂得感恩。
重点难点重点:学习生词和短语以及各连词引导的时间状语从句的用法。
难点:灵活使用生词、短语以及连词,学会使用时间状语从句。
教学准备PPT 课件;相关图片。
授课时数1课时教学过程Step 1 Lead-in1. Talk about Spud Webb.2. Revise the sentences with adverbial clauses of time in the passage about SpudWebb. Lead in the clauses.·While (he was) attending junior high, Spud tried out for the school team.·When he finally got the chance, he scored 20 points in his first game.·After he graduated, he was forced to play in another basketball league.·He remained there for about a year before the NBA took notice of him.Step 2 Grammar A1. Talk about the meanings and the uses of the conjunctions: before, after, when, while.(1)before意为“在……之前”, 表示主句动作发生在从句动作之前。
英语视听说2答案完整版
3.Turn left at the lights and then turn right
1B/5
stay
dinner
store
cook
place
drive
turn
straight
miss
find
Vocabulary and Usage
2A/5
3.Just press Ctrl+S
4.It doesn’t matter, on-line or off-line
5.Yes,I do,let me type it for you
Unit4
3/12
1.Emi need medicine
2.She is sick
5/12
reserve,browse,delete,fares
2/3
waitress
nervous
responsible
punctual
3/3
1.like
work
3.prescription
4.in your way
5.stufffed up
Grammar
6.You need to take it easy for a few days
11/12
More listening
1.Fever,headache,sore throat
2.For 2 or 3 days
3.Her throat hurts a lot
test
listening
3.Take Unibersity Avenue down….
外研版高一英语必修第二册(2019版)_Unit6_Using_language_公开课课件
3. Why does the author choose to use different forms of verbs in the two sentences? In sentence (a), a woman is swimming. In other words, the woman does the action of swimming. So the author uses -ing. But in sentence (b), people are frightened. As a result, passive voice is used. So the author uses -ed.
This includes keeping the original environment from being touched, ...
This includes keeping the original environment untouched, …
II Vocabulary building
1. In sentence (a), who is swimming at night? In sentence (a), a woman is swimming at night.
Grammar: -ing and -ed as complement Look at the sentences from the reading passage and answer the questions. a. We see a woman swimming at night in a dark sea. b. It made people frightened of sharks, ...
译林版英语四年级上册1到6单元作业
译林版英语四年级上册1到6单元作业Unit 1Homework 1: Listening Practice1. Listen to the audio and repeat the words.2. Practice saying the words in a sentence.Homework 2: Vocabulary Review1. Review the vocabulary words from the unit.2. Use the words to create sentences.Unit 21. Read the passage and answer the questions.2. Write a summary of what you learned from the passage.Homework 2: Grammar Practice2. Write five sentences using the grammar rules you learned.Unit 3Homework 1: Speaking Practice1. Find a partner and have a conversation using the vocabulary words from the unit.2. Practice asking and answering questions.Homework 2: Writing Practice1. Write a paragraph about your favorite hobby.2. Use the vocabulary words and grammar rules you learned in the unit.Unit 41. Listen to the audio and answer the questions.2. Practice listening to short conversations and understanding them.Homework 2: Vocabulary Expansion1. Find five new words related to the unit topic.2. Write sentences using the new words.Unit 51. Read the passage and answer the questions.2. Write a summary of the main ideas in the passage.Homework 2: Grammar Review1. Review the grammar rules from the unit.Unit 6Homework 1: Speaking and Writing Practice1. Have a conversation with a classmate about your favorite food.2. Write a paragraph describing your favorite food.Homework 2: Vocabulary and Grammar Consolidation1. Review the vocabulary and grammar rules from the unit.以上是《译林版英语四年级上册1到6单元作业》的内容。
Unit 2 We are friends!教案(第5课时 Grammar 2)-【中职专用】高一英
Unit 2 We are friends!教案(第5课时 Grammar 2)-【中职专用】高一英语同步精品课堂(外研版2021·基础模块1)教学目标:1.能够正确使用Can you和Yes, I can / No, I can't表达自己的能力。
2.能够运用Can you构造简单的疑问句和肯定/否定回答。
3.能够通过Can you与同伴进行简单对话,对自己的英语能力进行评价。
教学重点:能够准确使用Can you以及Yes, I can / No, I can't来表达自己的能力,并能够通过对话互相评价。
教学难点:学生可能在使用Yes, I can / No, I can't时会掌握不够准确,需要进行重点解释与练习。
教学准备:PPT、练习题。
教学过程:Step 1:Warming-up1.Greeting:T:Hello, everyone. Glad to see you today. How are you? Are you happy?Ss: Yes,I am.T: Well, today we are going to learn Unit 2 We are friends! Grammer2. Before that, can you say hello to your friends? Let's greet each other.Ss: Good morning, Mary. How are you?2. Revision:T: In the last lesson, we learned the use of 'Can'. Do you still remember? Here is an example:T: Can I speak to Mr. Wang? Yes, now you can say you have learned 'Can'. Congratulations! All the students say: YES!Step 2:Presentation1.Presentation:(PPT)(1)学习任务:1)能够准确使用Can you以及Yes, I can / No, I can't来表达自己的能力。
九年级英语下册unit2全套教案
九年级英语下册unit2全套教案9BUnit2welcometotheunitI.Teachingobjectives:.Tointroducethecontextabouthavingarobottohelpwiththe workforhumans2.Totalkaboutwhatarobotcando3.TolearnsomeoftheadvantagesofrobotsII.Teachingprocedure:Step1:warm-up:Toraisestudents’interest,getstudentsthinkingandtalkingaboutrobots:①Haveyouseenrobotsinthefilms?②whatkindofrobotsdoyouknow?③Doyoulikerobots?why?④whatdoyouthinkrobotscandoforyou?⑤wouldyoubuyarobotinthefuture?why?Step2:welcometotheunit.Thepurposeofthispartistoactivatestudent’sknowledgeofrobotsandgenerateinterestsofthistopic.Askonestudent toreadthephrasesinthewordboxatthetopofpage19.makesurethatall studentsunderstandthemeaningsofthephrasessuchas ‘dothelaundry,explorerdangerousplaces’intheirownwords.2.Explainthecontext.DanielisexplainingtoAmywhatrobotscando.AskstudentstocompletetheconversationonPage19onth eirown.3.Asktwostudentstoreadtheconversationandcheckmistakes.4.Encouragestudentstotalkaboutifrobotsareharmful?Divi destudentsintogroupstodiscuss.①whatdorobotsdoharmtohumanbeings?②whydotheydoharmtohumanbeings?5.Listentothetapeforthefirsttimetolearnthemainideaof thecomicstrip.6.Listentothetapeforthesecondtimetoreadafterthetape.7.Asksomestudentstoactoutthecomicstrip.Step3:Usefulexpressions.complaint:不+可数名词“抱怨”;可数名词“抱怨的行动或话,投诉”complain:动词:complainto/about2.post:动词‘邮寄’:.postsomethingforsb.III.Homework:.Recitetheusefulvocabularyandcomicstrip.2.completesomeexercise.3.Previewreading教学小结:学生基本能掌握对话,理解机器人能为人类做好多事。
Homework2
Solution of Homework 2Dragon:4.2.1, 4.2.4, 4.2.5, 4.2.74.3.14.4.3Tiger:3.4, 3.5, 3.6, 3.7Dragon Book4.2.1 Considering the context-free grammar:and the string aa+a*(1)Give a leftmost derivation of the string(2)Give a rightmost derivation of the string(3)Give a parse tree for the string(4)Is the grammar ambiguous?(5)Describe the language generated by the grammar答案:(1)(2)(3)SSS* S S+a aa(4)没有二义性(5)只含+和*,操作数均为a的算术表达式的后序遍历4.2.4 Show that [] and {} extension do not add power to grammars.答案: S->[a] 等价于S->S->{a} 等价于S->S’S’ -> ’4.2.5 Use notations from 4.2.4 to simplify the following grammar:答案:stmt-> if expr then stmt [else stmt]| begin stmtList endstmtList -> stmt{;stmt}4.2.7 A grammar symbol X (terminal or non-terminal) is useless if there is no derivation of the form . That is, X can neverappear in the derivation of any sentence.(1) Give an algorithm to eliminate all productions contains useless symbols(2) Apply your algorithm to grammar:S-> 0 | AA-> ABB->1答案:(1)注意:首先要考虑产生式是否终止,其次考虑是否在产生式中出现(a)求出非终结符是否终止对于每个非终结符X若X存在产生式不含非终结符,则X终止否则,对于X的每个产生式中的非终结符,若含有X,则X不终止,否则,若每个非终结符均终止,则X终止,否则不终止(b)去掉useless令文法G为空从起始的非终结符X开始对于X的每个产生式P,若P不含非终结符,则将X->P加入文法G否则,若P中每个非终结符均终止,则将X->P加入文法S’,并对每个非终结符X’递归调用这个过程返回文法G算法并不唯一,这只是一个很罗嗦的实现(2)对于这里给出的算法首先S和B终止,A不终止然后从S->0开始,S->0加入文法GS->A,A不终止,至此递归调用结束所以最终返回结果S->04.3.1 The following grammar for regular expressions over symbols a andb only.(1)Left factor this grammar(2)Does left factoring make the grammar suitable for top-down parsing?(3)Eliminate left recursion from the original grammar(4)Is the resulting grammar suitable for top-down parsing?答案:(1)rexpr -> rexpr + rterm | rtermrterm -> rterm rfactor | refactorrfactor -> rfactor * | rprimaryrprimary-> a| b(2)不可以,因为存在左递归(3)rexpr -> rterm rexpr’rexpr’-> + rterm rexpr’ |rterm-> rfactor rterm’rterm’ -> rfactor rterm’ |rfactor-> rprimay rfactor’rfactor’-> *rfactor’ |rprimary-> a | b(4)可以4.4.3 计算练习4.2.1中文法的FIRST和FOLLOW集合答案:FIRST(S)=aFOLLOW(S)= $a+*Tiger Book3.4 Write a grammar that accepts the same language as Grammar 3.1, but that us suitable for LL(1) parsing. That is, eliminate the ambiguity, eliminate the left recursion, and (if necessary) left-factor.Grammar 3.1:S -> S; SS -> id := ES -> print ( L )E -> idE -> numE -> E + EE -> ( S , E )L -> EL -> L , EAnswer:S -> id := E ; SS -> print ( L ) ; SE -> ( S , E )E -> id E’E -> num E’E’ -> εE’ -> + EL -> E L’L’ ->εL’ -> , E L’3.5 Find nullable, FIRST, and FOLLOW sets for the grammar; then construct the LL(1) parsing table.S’ -> S $S ->S -> X SB -> \ begin { WORD }E -> \ end { WORD }X -> B S EX -> { S }X -> WORDX -> beginX -> endX -> \ WORDAnswer:3.6a. Calculate nullable, FIRST, and FOLLOW for this grammar:S -> u B D zB -> B vB -> wD ->E FE -> yE ->F -> xF->b. Constructor the LL(1) parsing table.c. Give evidence that this grammar is not LL(1).d. Modify the grammar as little as possible to make an LL(1) grammar that accepts the same language.Answer:a)c) b中构建的LL(1)转换表中含有包含多个语法规则的表项,所以该语法不是LL(1)语法。
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Circle the verb and underline the subject, see if the subject and verb are in agreement. If the sentence is a fragment or if the sentence has error in subject verb agreement then rewrite it.
1)The traveling salesman was dismayed to learn that neither his sons or his daughter were
interested in moving.
2)I was so thirsty that either of the two drinks were fine with me.
3)A venomous snake designated the emblem of the rebellion by the insurgency.
4)A number of players on the team have improved since last season.
5)Jack, along with some of his closest friends, is sharing a limo to the prom.
6)The recent string of burglaries, in addition to poor building maintenances, have inspired the
outspoken resident to call a tenants meeting.
7)There is, according to my doctor, many courses of treatment available to me.
8)After all the gardening we did, the sun shining on the flowerbeds make a beautiful sight.
9)The placement of the unusual artwork in the mansion’s various rooms was impressive.
10)A new textbook focused on recent advances in artificial intelligence assigned by our
instructor.
11)Just around the corner is a fantastic bakery and a small supermarket.
12)Planting all these seeds is more involved than I thought.
13)Whoever rented these movies has to take them back before midnight
14)Tired of practicing, the orchestra decided to walk out on their astonished conductor.
15)The proliferation of computer games designed to involve many players at once were first
developed before the widespread availability of high-speed internet connections.
Circle the parallelism markers and place brackets around each set of parallel elements. Rewrite the sentence with parallelism errors.
1)Researchers have found a correlation between exercise and earning good grades.
2)Although we were sitting in the bleachers, the baseball game was as exciting to us as the
people sitting behind home plate.
3)Many teachers choose to seek employment in the suburbs rather than facing low salaries in
the city.
4)A good night’s sleep not only gives your body a chance to rest, but also energizing you for the
following day.
5)The joint business venture will increase employee satisfaction and be improving relations
between upper management and staff.
6)The museum displays the work of a wide variety of artists, from those who are
world-renowned to who are virtually unknown.
7)We were dismayed to learn that our neighbors were untidy, disagreeable, and they were
uninterested to make new friends.
8)The students did poorly on the test more because they had not studied than the material was
difficult.
9)The blizzard deposited more than a foot of snow on the train tracks, prompted the transit
authority to shut down services temporarily, and causing discontent among commuters who were left stranded for hours.
10)The experience we have when children influence our behavior in adulthood.
11)The band chosen for the annual spring concert appealed to both the student body as well as
the administration.
12)Tobacco companies shaken by a string of legal setbacks in the United States, but which retain
strong growth prospects in the developing world, face an uncertain future.
13)V oters want to elect a president who genuinely cares about health care, the environment, the
travails of ordinary men and women, has the experience, wisdom, and strength of character required for the job.
14)The consultant is looking for a café where there are comfortable chairs and that provides free
internet access.
15)Dr. Crock’s claims have been not corroborated by other scientists or published in a prestigious
journal but have nonetheless garnered a great deal of attention from the public.。