高考情態(tài)動詞的用法及區(qū)別

1、高中情態(tài)動詞的用法及區(qū)別首先它是動詞,而且不同于行為動詞,行為動詞表示的是可以通過行為來表達(dá)的動作(如寫,讀,跑,而情態(tài)動詞只是表達(dá)的一種想法(如能,也許,敢。用法是:情態(tài)動詞+行為動詞原形例句:I can read this sentence in English.我能用英語讀這句話。情態(tài)動詞是一種本身有一定的詞義,表示說話人的情緒,態(tài)度或語氣的動詞,但不能單獨作謂語, 只能和其他動詞原形構(gòu)成謂語。We can be there on time tomorrow.我們明天能按時去那兒。May I have your name? 我能知道你的名字嗎?Shall we begin now?我們現(xiàn)

2、在就開始嗎?You must obey the school rules.你必須遵守校規(guī)。情態(tài)動詞數(shù)量不多,但用途廣泛,主要有下列:can (could, may (might, must, need, ought to, dare (dared, shall (should, will (would,have (to ,had better.情態(tài)動詞還有一個很重要的用法,即情態(tài)動詞表推測情態(tài)動詞表推測的用法小結(jié)(一情態(tài)動詞表推測的三種句式1.在肯定句中一般用must (一定,may(可能,might / could(也許,或許。(1He must/may/might know the ans

3、wer to this question?他一定/可能/也許知道這個問題的答案。(2It is cold in the room. They must have turned off the heating.屋里很冷,他們肯定把暖氣關(guān)了。2.否定句中用cant / couldnt(不可能, may not/might not(可能不。(1It cant/couldnt be the headmaster. He has gone to America.這不可能是校長,他去美國了。(2He may not/might not know the scientist.他也許不認(rèn)識那位科學(xué)家。3.疑問

4、句中用can/could (能?。(1Could he have finished the task?他可能把任務(wù)完成了嗎?(2Can he be at home now?他現(xiàn)在能在家嗎?注:以上三種句式中情態(tài)動詞的語氣按程度都是依次遞減的。Might, could并非may, can的過去式,而表示語氣較為委婉或可能性較小。(二情態(tài)動詞表推測的三種時態(tài)1.對將來情況的推測,用“情態(tài)動詞+ 動詞原形”。(1She must / may / might / could arrive before 5.5:00前她一定/可能/也許到。(2She must/may/might/could walk

5、miles and miles among the hills without meeting anyone.她一定/可能/也許會在山里一連走好幾英里而遇不到一個人。2.對現(xiàn)在或一般情況的推測,用“情態(tài)動詞+ be”,“情態(tài)動詞+be doing”或“情態(tài)動詞+ 動詞原形”。(1He must / may / might / could be listening to the radio now.他一定/可能/也許正在聽收音機(jī)。(2He cant ( couldnt / may ( might not be at home at this time.這個時候他不可能/可能不在家。(3Mr. B

6、ush is on time for everything .How can ( could he be late for the opening ceremony ?布什先生一向準(zhǔn)時,這次開幕式他怎么可能遲到呢?3.對過去情況的推測,用“情態(tài)動詞+ have +過去分詞”。(1It must / may / might / could have rained last night .The ground is wet.地濕了,昨晚肯定/可能/也許下雨了。(2The door was locked. He can ( could not / may ( might not have been

7、at home .門鎖著,他不可能/可能不在家。(3Can / Could he have gotten the book?難道他找到書了嗎?注:情態(tài)動詞should /ought to表推測時,意為“想必會,理應(yīng)”但與“have +過去分詞”連用時,則又可構(gòu)成虛擬語氣意為“本應(yīng)該做某事卻沒做”。例如:(4Its seven oclock. Jack should/ought to be here at any moment.現(xiàn)在七點鐘了,杰克理應(yīng)隨時到達(dá)。(推測(5She should / ought to have attended your birthday party, but she

8、 had to look after her mother in hospital. (虛擬她本該出席你的生日晚會的,可是她得在醫(yī)院照顧她媽媽。(6Tom should not /ought not to have told me your secret, but he meant no harm. (虛擬湯姆本不該告訴我你的秘密,可是他并無惡意。情態(tài)動詞有can (could, may (might, must, have to, shall (should, will (would, dare (dared, need (needed, ought to等。情態(tài)動詞無人稱和數(shù)的變化;不能單

9、獨使用,必須與其后的動詞原形構(gòu)成謂語一、can, could1 表示能力(體力、知識、技能。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。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)。Ill not be able to come this afternoon.當(dāng)表示“經(jīng)過努力才得以做成功某事”時應(yīng)用be able to,不能用Can。如:He was able to go to the party yesterday

10、 evening in spite of the heavy rain.2 表示請求和允許。-Can I go now?- Yes, you can. / No, you cant.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。- 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 changed the timetable, so we can go by bus instead.T

11、his 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?二、may, 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, you mustnt.- May/Might I take this book out of the

12、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。1.He may /might be very busy now.2.Your mother may /might not know the truth.三、must, have to1 表示必須、必要。You must come in time.在回答引出的問句時,如果是否定的,不能用

13、mustnt(禁止,不準(zhǔn),而用neednt, dont have to(不必. - 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(qiáng)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。1.he play isnt interesting, I really must go now.2.I had to work when I was your age.3 表示推測、可能性(只用于肯定的陳述

14、句1.Youre Toms good friend, so you must know what he likes best.2.Your mother must be waiting for you now.四、dare, 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。1.How dare you say Im unfair?2.He darent speak En glish before such a crowd, dare he?3.If we dared not go there that day,we couldnt get th

15、e 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。1.You 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 s

16、wim across this river.2. He doesnt dare (to answer.3. He needs to finish his homework today.五、shall, 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 work hard.(警告2. He shall have the book when I finish it.(允諾3. He shall b

17、e punished.(威脅六、will, 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 abroad.3 would表示過去反復(fù)發(fā)生的動作或某種傾向。would表示過去習(xí)慣時比used to正式,且沒有“現(xiàn)已無此習(xí)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.七、should, ought to1 should, ought to表示“應(yīng)該”,ought to表示義務(wù)或責(zé)任,比should語氣重。1. I should help her because she is in trouble.2. You ought to take care of the