第13講情態(tài)動詞

1、第13講情態(tài)動詞1.英語情態(tài)動詞 can ; could; may; might; will; would; shall; should; must; need;have to; ought to.情態(tài)動詞沒有人稱，數的變更，即情態(tài)動詞加do.A 比較 can 和 be able to1） can /could表示能力；可能（過去時用could）,只用于現在式和從前式（could）。be able to能夠用于各種時態(tài)。They will be able to tell you the news soo n. 他很快就能告訴你消息了。2）表示成功地做了某事時，只能用 was/were able

2、 to， 不能用could。He was able to flee Europe before the war broke out.=He man aged to flee Europe before the war broke out.could不表示時態(tài)內容來自1 ）提出委婉的懇求，（留神在答復中不可用could ）。-Could I have the televisi on on?-Yes, you can. / No, you can't.2）在否定，疑問句中表示推測或猜疑He could n't be a bad man.B比較 may和 might內容來自1）表示請

3、求允許；表示 推測；He might be at home.May I come in ?初中英語情態(tài)動詞注意：might表示推測時，不表示時態(tài)。只是可能性比may小。may/might as well，后面 do, 意為"不妨"If that is the case, we may as well try.Petercome with us toni ght, but he isn't very sure yet.A. mustB. may C. canD. willC 比較 have to 和 must1. have to表示客觀的須要，must表示談話人主觀上

4、的看法，既主觀上的必要。My brother was very ill, so I had to call the doctor in the middle of the ni ght.He said that they must work hard.2. have to有人稱、數、時態(tài)的變化，而must只有一種形式。He had to look after his sister yesterday.3. 在否定構造中：don't have to 表示"不必"must n't表示"禁止"，You don't have to tel

5、l him about it.You must n't tell him about it.4. must表示推測1) must用在肯定句中表示較有把握的推測，意為"一定"。2) must表對現在的狀態(tài)或現在正產生的事件的推測時，must后面通常接系動詞be的本相或舉動動詞的進行式。You have worked hard all day. You must be tired.內容來自He must be worki ng in his office.3) 否定推測用can't。If Tom did n't leave here un til fiv

6、e o'clock, he can't be home yet.D should 跟 ought to ； ought to 在語氣上比 should 要強。should和ought to都為"應當”的意思，可用于各種人稱。-Ought he to go?-Yes. I think he ought to.表示命令時，語氣由 should (應該)、had better最好)、must (必須)漸強E . had better 表示"最好"had better 它后面要跟動詞原形had better do sth/ had better n ot

7、do sthIt is pretty cold. You'd better put on my coat. 內容來自She'd better not play with the dog.F. will 和 would1)would like ； Would like to do = want to 想要，為固定搭配。Would you like to go with me? 表示委婉語氣2) Will you ？ Would you like?Would you like some cake?G 情態(tài)動詞的回答萬式 問句Need I go home now ? Must you

8、 do your work now?肯定回答Yes , you must. /Yes, I must/否定回答No , you n eed n'tNo, I don't have to. / needn '1)-Could I borrow your dict ion ary?-Yes, of course, you.A. mightB. willC. can D. should2) -Shall I tell John about it?-No, you.I've told him already.A. need n'tB. would n'tC. must n'tD. should n't3) -Don't forget to come to my birthday party tomorrow.-A. I don'tB. I won'tC. I ca n'tD. I have n't 內容來H 比較 need 和 dare m兩詞既可做實義動詞用，又可做情態(tài)動詞用。作為情態(tài)動詞，兩者