知识讲解及情态动词用法

1、.Module 5 知识辅导Language points:1. You mustnt go off on your own.Go off 意思是“分开， 走开。On ones own 意思是“单独。例如： He lives on his own.I need some time on my own.2. You must keep to the path.Keep to 的意思是“沿着走； 使不分开； 留在某个位置。例如：Lets keep to the point or well never reach any decisions.Please keep to the left hand

2、side of the stairs. 3. Im starving! 我都快饿死了！在非正式英语中，当人们想表达“非常饿这个概念的时候， 常说“Im starving!例如：Whats for lunch? Im starving! 4. Come on! Ill lead the way.这里lead 表示“带路， 领路。例如：I dont know the way, so youd better lead.You lead on and well follow behind on the horses.Come on 在不同的情境有不同的意思。例如：Come onwere going t

3、o be late if you dont hurry! 快点 Your piano playing has really come on since I last heard you play. 有进步- Itll take at least two hours to do this!- Oh, come on! I could do it in 20 minutes.得啦！算了吧！5. On our first evening, the three of us were tired after walking for about eight hours.在本句中，the 用在数词前，表示特

4、指。the three of us 指的是“我们三个人一共就三个人。而three of us 那么说的是“我们中的三个不止三个人。再如：They have eight people in the team. The eight of them all know only good teamwork will enable them to get the job done on time. 这个小组有八个人。这八个人都知道，只有精诚合作，他们才能按时完成任务。There are 10 people in the office and eight of them are women. 办公室里有1

5、0个人，其中八个是女士。6. if I reach out, I can just touch him.这里reach out 表示“伸出手臂。例如：The monkey reached out a hand for the banana.He reached his hand out for the phone and knocked over a glass.7. For the next 10 days, every time there was a sudden noise, my blood went cold.这里go表示“处于某种状态，尤指令人生厌的状态，其后可以接形容词，如本句

6、中的cold。例如：When the crops fail, the people go hungry.I always go red when Im embarrassed.Wed better eat these apples before they go bad.every time 在句中引导一个状语从句，表示“每次, 每当。例如：Every time I go and see him, hes always working in the room.8. The first rule of camping is to keep a clean camp site.这个句子中不定式作表语

7、，又如：To save water is to save our lives.9. You cant leave anything which bears might think is food.这里which bears might think is food是一个定语从句，修饰anything。10. 注意本课出现的表达不同时间段的短语：on our first eveningin the middle of the night in the morning later that day during the night the next day for the next 10 days

8、grammar:情态动词的语法特征1 情态动词不能表示正在发生或已经发生的事情，只表示期待或估计某事的发生。2 情态动词 除ought 和have 外，后面只能接不带to 的不定式。3 情态动词没有人称，数的变化，即情态动词第三人称单数不加-s。4 情态动词没有非谓语形式，即没有不定式，分词，等形式。比较can 和be able to1cancould 表示才能；可能 过去时用could, 只用于如今式和过去式could。be able to可以用于各种时态。They will be able to tell you the news soon. 他很快就能告诉你消息了。2只用be able

9、to a. 位于助动词后。 b. 情态动词后。 c. 表示过去某时刻动作时。 d. 用于句首表示条件。 e. 表示成功地做了某事时，只能用was/were able to， 不能用could。He was able to flee Europe before the war broke out.= He managed to flee Europe before the war broke out.注意：could不表示时态1提出委婉的恳求，注意在答复中不可用could。 - Could I have the television on? - Yes, you can. / No, you c

10、an't.2在否认，疑问句中表示推测或疑心。 He couldn't be a bad man. 他不大可能是坏人。比较may和might1 表示允许或恳求；表示没有把握的推测；may 放在句首，表示祝愿。May God bless you!He might be at home.注意： might 表示推测时，不表示时态。只是可能性比may 小。2 成语： may/might as well，后面接不带to 的不定式，意为"不妨"。 If that is the case, we may as well try.典型例题Peter _come with u

11、s tonight, but he isn't very sure yet. A. mustB. may C. can D. will答案B. 表可能性只能用may.此句意可从后半句推出。比较have to和must1两词都是'必须'的意思，have to 表示客观的需要， must 表示说话人主观上的看法，既主观上的必要。My brother was very ill, so I had to call the doctor in the middle of the night.我弟弟病得很厉害，我只得半夜里把医生请来。客观上需要做这件事He said that th

12、ey must work hard. 他说他们必须努力工作。主观上要做这件事 2have to有人称、数、时态的变化，而must只有一种形式。但must 可用于间接引语中表示过去的必要或义务。He had to look after his sister yesterday.3 在否认构造中： don't have to 表示"不必"mustn't表示"制止"， You don't have to tell him about it. 你不一定要把此事告诉他。 You mustn't tell him about it.你

13、一定不要把这件事告诉他。must表示推测1 must用在肯定句中表示较有把握的推测，意为"一定"。2 must表对如今的状态或如今正发生的事情的推测时， must 后面通常接系动词be 的原形或行为动词的进展式。 You have worked hard all day. You must be tired. 你辛苦干一整天，一定累了。对如今情况的推测判断He must be working in his office. 他一定在办公室工作呢。比较： He must be staying there. 他如今肯定呆在那里。 He must stay there. 他必须呆在

14、那。 3 must 表示对已发生的事情的推测时，must 要接完成式。 I didn't hear the phone. I must have been asleep.我刚刚没有听到 ，我想必是睡着了。4 must表示对过去某时正发生的事情的推测，must 后面要接不定式的完成进展式。-Why didn't you answer my phone call?-Well, I must have been sleeping, so I didn't hear it.5 否认推测用can't。 If Tom didn't leave here until

15、five o'clock, he can't be home yet.假如汤姆五点才分开这儿，他此时一定还未到家。表示推测的用法can, could, may, might, must 皆可表示推测，其用法如下：1情态动词+动词原形。表示对如今或将来的情况的推测，此时动词通常为系动词。I don't know where she is, she may be in Wuhan.2情态动词+动词如今进展时。表示对如今或将来正在进展的情况进展推测。At this moment, our teacher must be correcting our exam papers.这

16、时，我们老师想必在修改试卷。3情态动词+动词完成时。表示对过去情况的推测。We would have finished this work by the end of next December.明年十二月底前我们很可能已完成这项工作了。The road is wet. It must have rained last night.地是湿的，昨天晚上一定下雨了。4情态动词+动词的如今完成进展时。表示对过去正在发惹事情的推测。Your mother must have been looking for you.你妈妈一定一直在找你。5推测的否认形式，疑问形式用can't, couldn&

17、#39;t表示。Mike can't have found his car, for he came to work by bus this morning.迈克一定还没有找回他的车，因为早上他是坐公共汽车来上班的。注意：could, might表示推测时不表示时态，其推测的程度不如can, may。情态动词+ have +过去分词1 maymight have + done sth, can could have + done sth表示过去，推测过去时间里可能发生的事情。Philip may might have been hurt seriously in the car acc

18、ident.Philip can could have been hurt seriously in the car accident.2must have +done sth，对过去时间里可能发生的事情的推测，语气较强，具有"肯定"，"谅必"的意思。-Linda has gone to work, but her bicycle is still here.-She must have gone by bus.3 ought to have done sth, should have done sth本应该做某事，而事实上并没有做。否认句表示"

19、;不该做某事而做了"。You ought to should have been more careful in this experiment.He ought not to have thrown the old clothes away.事实上已扔了。ought to 在语气上比should 要强。4 needn't have done sth 本没必要做某事I dressed very warmly for the trip, but Ineedn't have done so. The weather was hot.5 would like to have

20、 done sth 本打算做某事I would like to have read the article, but I was very busy then.should 和ought toshould 和ought to 都为"应该"的意思，可用于各种人称。-Ought he to go?-Yes. I think he ought to.表示要求，命令时，语气由 should应该、had better最好、must必须渐强。had better表示"最好"had better 相当于一个助动词，它只有一种形式，它后面要跟动词原形。had bette

21、r do sth had better not do sthIt is pretty cold. You'd better put on my coat.She'd better not play with the dog. had better have done sth表示与事实相反的结果，意为"本来最好"。You had better have come earlier.would rather表示"宁愿"would rather dowould rather not dowould rather than 宁愿而不愿。还有woul

22、d sooner, had rather, had sooner都表示"宁愿"、"宁可"的意思。If I have a choice, I had sooner not continue my studies at this school.I would rather stay here than go home. = I would stay here rather than go home.典型例题-Shall we go skating or stay at home?-Which _ do? A. do you ratherB. would yo

23、u rather C. will you rather D. should you rather答案B。此题考察情态动词rather的用法，would rather +do sth 意为"宁愿"，此题为疑问句，would 提早，所以选B。will和would注意： 1would like； Would like to do = want to 想要，为固定搭配。 Would you like to go with me?2Will you?Would you like? 表示肯定含义的恳求劝说时，疑问句中一般用some, 而不是any。 Would you like som

24、e cake?3否认构造中用will，一般不用would, won't you是一种委婉语气。 Won't you sit down?情态动词的答复方式问句肯定答复否认答复Need you?Yes, I must.No, I needn'tMust you?/don't have to. 典型例题1-Could I borrow your dictionary?-Yes, of course, you_. A. mightB. will C. can D. should 答案C. could表示委婉的语气，并不为时态。答语中of course，表示肯定的语气，允

25、许某人做某事时，用can和 may来表达，不能用could或might。复习： will 与you连用，用来提出要求或下命令。should与you 连用，用来提出劝告。2-Shall I tell John about it?-No, you _. I've told him already. A. needn'tB. wouldn'tC. mustn'tD. shouldn't 答案A。needn't 不必，不用。 wouldn't 将不, 不会的。 mustn't 制止、不能。 shouldn't不应该。此题为不需要，不必的意思，应用needn't。3-Don't forget to come to my birthday party tomorrow.-_.A. I don't B.I won't C. I can'tD. I haven't 答案B.will既可当作情态动词，表恳求、建议、也可作为实义动词表"意愿、意志、决心"，此题表示决心，选B。带to 的情态动词带to 的情态