情態(tài)動詞思維導圖(共3頁)

1、精選優(yōu)質(zhì)文檔-傾情為你奉上情態(tài)動詞無人稱和數(shù)的變化；不能單獨使用，必須與其后的動詞原形構(gòu)成謂語01can, could1) 表示能力（體力、知識、技能） Can只有一般現(xiàn)在時和一般過去式；而be able to則有更多的時態(tài)。Can you lift this heavy box?（體力） Mary can speak three languages.（知識） Can you skate?（技能）此時可用be able to代替。 Ill not be able to come this afternoon. 當表示“經(jīng)過努力才得以做成功某事”時應用be able to，不能用Can。 如：

2、He was able to go to the party yesterday evening in spite of the heavy rain.2) 表示請求和允許。此時可與may互換。在疑問句中還可用could,might代替，不是過去式，只是語氣更委婉，不能用于肯定句和答語中。-Can I go now? - Yes, you can. / No, you cant. - Could I come to see you tomorrow? - Yes, you can. ( No, Im afraid not. )3) 表示客觀可能性（客觀原因形成的能力）Theyve change

3、d the timetable, so we can go by bus instead.This hall can hold 500 people at least. 4) 表示推測（驚訝、懷疑、不相信的態(tài)度），用于疑問句、否定句和感嘆句中。Can this be true? This cant be done by him.How can this be true?02may, might1) 表示請求和允許。might比 may語氣更委婉，而不是過去式。否定回答時可用cant或mustnt，表示“不可以，禁止”。-Might/ May I smoke in this room? - No

4、, you mustnt.- May/Might I take this book out of the room? - Yes, you can. (No, you cant / mustnt. ) 用May I.？征徇對方許可時比較正式和客氣，而用Can I.？在口語中更常見。2）用于祈使句，表示祝愿。May you succeed!3) 表示推測、可能性（不用于疑問句）。might不是過去式，它所表示的可能性比may小。1He may /might be very busy now. 2Your mother may /might not know the truth.03must, h

5、ave to1) 表示必須、必要。在回答引出的問句時，如果是否定的，不能用mustnt（禁止，不準），而用neednt, dont have to（不必）.You must come in time.- Must we hand in our exercise books today? - Yes, you must. - No, you dont have to / you neednt.2) must是說話人的主觀看法， 而have to則強調(diào)客觀需要。Must只有一般現(xiàn)在時， have to 有更多的時態(tài)形式。1he play isnt interesting, I really mus

6、t go now.2I had to work when I was your age.3) 表示推測、可能性（只用于肯定的陳述句）1 Youre Toms good friend, so you must know what he likes best. 2Your mother must be waiting for you now.04dare, need1) dare作情態(tài)動詞用時, 常用于疑問句、否定句和條件從句中, 過去式形式為dared。1How dare you say Im unfair? 2He darent speak English before such a crow

7、d, dare he?3If we dared not go there that day， we couldnt get the beautiful flowers.2) need 作情態(tài)動詞用時, 常用于疑問句、否定句。在肯定句中一般用must, have to, ought to, should代替。1You neednt come so early.2. - Need I finish the work today? - Yes, you must. / No, you neednt.3) dare和 need作實義動詞用時， 有人稱、時態(tài)和數(shù)的變化。在肯定句中，dare后面常接帶to

8、的不定式。在疑問句和否定句中，dare后面可接帶to或不帶to的不定式。而need后面只能接帶to的不定式。1. I dare to swim across this river.2. He doesnt dare (to) answer.3. He needs to finish his homework today.05shall, should1) shall 用于第一人稱，征求對方的意見。What shall we do this evening?2) shall 用于第二、三人稱，表示說話人給對方的命令、警告、允諾或威脅。1. You shall fail if you dont w

9、ork hard.(警告) 2. He shall have the book when I finish it.(允諾)3. He shall be punished.(威脅)情態(tài)動詞無 人 稱 和 數(shù) 的 變化；不 能 單 獨 使用，必 須 與 其 后 的 動 詞 原 形 構(gòu) 成 謂 語06will, would1) 表示請求、建議等，would更委婉。Will / Would you pass me the ball, please?2) 表示意志、愿望和決心。1. I will never do that again.2. They asked him if he would go a

10、broad.3) would表示過去反復發(fā)生的動作或某種傾向。would表示過去習慣時比used to正式，且沒有“現(xiàn)已無此習慣”的含義。1. During the vacation, he would visit me every other day.2. The wound would not heal.4) 表示估計和猜想。It would be about ten oclock when she left home.07hould, ought to1) should, ought to表示“應該”，ought to表示義務或責任，比should語氣重。1. I should help

11、 her because she is in trouble.2. You ought to take care of the baby.2) 表示勸告、建議和命令。should, ought to可通用，但在疑問句中常用should。1. You should / ought to go to class right away.2. Should I open the window?3) 表示推測should , ought to (客觀推測), must(主觀推測)。1. He must be home by now. (斷定他已到家)2. He ought to/should be ho

12、me by now.(不太肯定)3. This is where the oil must be.(直爽)4. This is where the oil ought to/should be.(含蓄)08情態(tài)動詞+不定式完成式（have done）1) can / could + have done在肯定句中表示“本來可以做而實際上能做某事”，是虛擬語氣；在疑問句或否定句中表示對過去行為的懷疑或不肯定, 表示推測。1. You could have done better, but you didnt try your best. （虛擬語氣）2. He cant have been to

13、that town.（推測）3. Can he have got the book?（推測）2) may / might +不定式完成式（have done）表示對過去行為的推測。不能用于疑問句中，沒有虛擬語氣的用法。Might所表示的可能性比may小。1.He may not have finished the work . 2.If we had taken the other road, we might have arrived earlier.3）must +不定式完成式（have done）用于肯定句中，表示對過去行為的推測。意為“一定、想必”。其疑問、否定形式用can，cant代

14、替。參看1) can / could + have done表示推測。1.You must have seen the film Titanic.2.He must have been to Shanghai.4）should +不定式完成式（have done） 用于肯定句中，表示對過去行為的推測。He should have finished the work by now。 表示“本應該做而實際上沒有做某事”，其否定式表示某種行為本不該發(fā)生卻發(fā)生了?？梢耘cought to +不定式完成式（have done）互換。1.You ought to / should have helped him. (but you didnt.)2.She shouldnt have taken away my measuring ta