超级全的情态动词所有整理

情态动词

? 英语助动词（auxiliaries）主要有两类，基本助动词(primary auxiliaries)和情态动词(modal auxiliaries)。 ? 基本助动词有三个，即do, have 和be。

? 情态动词有九个，它们是:can, may, must, ought to, shall, will, need, dare, used to等等。

加上过去式共十三个，could,might,should,would

Can 能，可能

固定搭配：cannot (help) but do=can`t help doing 不得不，只能 can’t/couldn't+不定式完成体”结构

1. “can?t/can have done”结构表示以“现在”为出发点，推侧过去某种“动作”发生了，多用于否定句和疑问句中，意为“很可能……了?，“不太可能……”等。如:

Her interference can have done a great deal of harm. 她的干涉可能已造成巨大伤害.

She can?t have written this because it is in French and she doesn't know French. 这不可能是她写的，因为这是用法文写的，而她不懂法文

2.在疑问句或否定句中，”can +不定式完成体”结构表示语气很强的猜侧或推断。 如:Can he have made a mistake? 他会弄错了吗?(含义是:他不可能搞错的) 比较：Could he have made a mistake?他会弄错了吗? (一般性推测)

He can' t have made a mistake.他肯定不会弄错。 Can和could同样用于比较的时候，can的语气更强烈 3. “could/couldn`t+不定式完成体”表示以“过去”为起点

Could have done 虚拟语气用法：本来可以，本来会，本来能（事实上没有） 推测：有可能

Couldn`t have done 虚拟语气用法：本不会，本不能（实际上已经做了） 推测：不会，不可能

Tom could have broken the glass. He was the only one at home yesterday. 汤姆可能打破了这个玻璃杯 Mary couldn`t have bolded the door.玛丽不可能把门闩上。（栓上了）

May 可能会，或许会

固定搭配：may/might (just) as well 不妨 may…but 可能…但是 may well 很可能

try as…may 尽管…（也不能）

1．“may /might+不定式完成体”结构可以用来表示对过去事物

①怀疑和推侧，不过might比may表示的可能性较小，语气更加委婉：可能/或许已经.. 有抱怨或批评之意 ②Might have done 还有虚拟语气用法：表示过去有可能发生（但实际没有发生），常用来表示埋怨 2．当不能肯定过去某动作是否发生时，用“may+不定式完成体”. 但这种确定性不复存在时，应该用“might+不定式完成体?。如:

You shouldn?t have drunk the wine. It may have been drugged.. 你不该喝了那酒，或许酒里有麻醉药呢。(说话者不能肯定酒里是否有麻醉药)

You shouldn?t have drunk the wine. It might have been drugged. 你不该喝了那酒，要是酒里有麻醉药呢。(说话者肯定酒里是没有麻醉药)

Must 必须，一定，Mustn`t 禁止，一定不要

“must+不定式完成体”，意为?一定，肯定，准是?，表示对过去某一行为的肯定推侧，即说话人确信这一行为的发生有极大的可能性。如:

Tom was absent yesterday. He must have been ill.汤姆昨天没来, 他肯定是生病了。

You? re on time. You must have got up very early today.你来得准时。今天你一定起来得很早。 Can`t/couldn`t have done与must have done 相对

Must表肯定猜测He must be ill, he looks so pale.他一定生病了，他的脸色很苍白

Can`t表否定猜测He can?t be on the sports ground now, I saw him just now in the library. 他现在不可能在操场上，刚刚我在图书馆见过他。

ought to 应该，应当Should 应该，应当

过去式还是ought to,否定式oughn`t to Should have done/ought to have done ① 对过去的推测用法：应该（已经）

Aren't you tired? I ____ you had done enough for today. A. should have thought B. must have thought C. might have thought D. could have thought ② 虚拟语气用法：应该做的没有做，本应该…

不应该做的做了，是否定，用 shouldn`t have done/oughtn`t to have done Ought to强调责任，义务或应该做的事

should表示适宜做某事，有时表示事情的必然性

would have done 与could have done的区别

? “would have done” 强调“本来想，希望做而没有做”。 ? “could have done” 强调“本来能够做某事而没有做”。 ① 表示“本来想做而却未做的事”

I would have told you all about the boy's story, but you didn't ask me. ② 对过去情况的虚拟描述

He must have had an accident,or he would have been here then.

Need和dare既可做实义动词也可作情态动词

Need的基本用法

① 做情态动词，没有人称，数，时态变化，后接动词原形，否定式为needn`t 做情态动词时一般用在否定和疑问句中need do 做实义动词，一般肯定句用need to do

Needn`t have done过去本不必做的事情，但实际上做了=didn`t have to do

? didn' t need+不定式一般式”和need用作情态动词时的“needn?t + 不定式完成体”结构都可以表示过去，但是意义却有不同。前者指动作还没有发生。如:

? I didn?t need to go to the station. 我本来不需要去车站（只是强调事实：去车站是没有必要的，至于“我”去没去车站不得而知）。

? I needn?t have gone to the station. 我本来用不着到车站去〔“我”事实上已经去火车站了)。

\不定式完成体?还经常与“could+不定式完成体”连用。如： You needn' t have typed it twice. You could have used a carbon.你用不着打两遍，你本来可以用复写纸写嘛。 You needn? t have walked up. You could have taken the lift. 你用不着走上来，你本来可以坐电梯的。 ② 做实义动词，有人称、数和时态变化，

need to do 否定在前面加don`t/doesn`t 疑问句用do,does,did提问 Need doing=need to be done Dare的基本用法

① 做情态动词，没有人称、数的变化。可以有过去式dared