情态动词表推测用法总结(整理稿)

补充强调：推测的句型特点(对某一次的推测句型有两部分：语气和时态)

(1)语气部分：(以下情态动词语气由强至弱)

肯定句：must、may might ( =could)

否定句：can，t ( =couldn 't )、mayn t> mightn 't

疑问句：can> could (语气更加委婉不确定

(2)时态部分：

have done 表示对过去的推测

be doing 表示对正在进行的推测

be表示对现在的推测

语气部分写在前时态部分写在后，组合在一起就是推测

(-)情态动词表推测的三种句_

能用于表推测的情态动词:must, can, could, will, would, may, might, should, ought to

1. 在肯定句中一般用must (一定)，may (可能)，might / could (也许，或许)。

(1)He must/may/might know the answer to this question? 他一定/可能/也许知道这个问题的答案。

(2)It is cold in the room・ They must have turned off the heating・

屋里很冷，他们肯定把暖气关了。

2. 否定句中用can't / couldn 't (不可能)，may not/might not (可能不)。

(1)It can J t/couldn 't be the headmaster・ He has gone to America.这不可能是校长，他去美国了。

(2)He may not/might not know the scientist.

他也许不认识那位科学家。

3. 疑问句中用can /could (能..?)。

(1) Could he have finished the task?

他可能把任务完成了吗？

(2) Can he be at home now?

他现在能在家吗？

注：以上三种句式中情态动词的语气按程度都是依次递减的。Might, could并非的过may, can 去式，而表示语气较为委婉或可能性较小。

(二)情态动词表推测的三种时丄

1.对将来情况的推测，用丨“情态动词+动词原形”。

(1) She must / may / might / could arrive before 5. 5:00前她一定/可能/也许到。

(2) She must/may/might/could walk miles and miles among the hills without meeting anyone・她一定/ 可能/也许会在山里一连走好几英里而遇不到一个人。

(1)He must / may / might / could be listening to the radio now.

他一定/可能/也许正在听收音机。

(2)He can't ( couldn 't ) / may ( might ) not be at home at this time.

这个时候他不可能/可能不在家。

(3)Mr. Bush is on time for everything . How can ( could ) he be late for the opening ceremony 布

什先生一向准时，这次开幕式他怎么可能迟到呢？

3•对过去情况的推测，用丨“情态动词+ have +过去分词”丨。

(1)It must / may / might / could have rained last night .The ground is wet.

地湿了，昨晚肯定/可能/也许下雨了。

(2)The door was locked. He can ( could ) not / may ( might ) not have been at home .

门锁着，他不可能/可能不在家。

(3)Can / Could he have gotten the book ?

难道他找到书了吗？

注：情态动词should / ought to 表推测时，意为"想必会，理应”但与"have +过去分词”连

用时，则又可构成虚拟语气意为“本应该做某事却没做”。例如：

(4)It 's seven o 'clock. Jack should/ought to be here at any moment.

现在七点钟了，杰克理应随时到达。(推测)

(5)She should / ought to have attended your birthday party, but she had to look after her

mot her in hosp it al. (虚拟)

她本该出席你的生日晚会的，可是她得在医院照顾她妈妈。

(6)Tom should not /ought not to have told me your secret, but he meant no harm. (虚拟)

汤姆本不该告诉我你的秘密，可是他并无恶意。

(三)几组表推测的情态动词用法

情态动词+完成时”是历年高考的热点，在做此类练习时，既需要掌握这一结构的基本用法，又应该仔细体会题干所提供的语言信息，准确理解语言环境和说话人的含义，尤其要注意题干中时态给予的暗示。

1. must have done表示对已经发生的事情的推测，意为一定，想必”，句子中表示的是一-种肯定的推测。

这种结构一般只用于肯定句，其否定形式是can，t (couldn ')thave done,表示不可能，肯定不会”。例

如：

He didn ' t hear the phone ・ He must have been asleep・

他没有听到电话响，他肯定是已经睡着了。

He must have bee n to Shan ghai・

他一定去过上海。

They can 't have gone out , because the light is on .