3. 表推测的情态动词must, may, can, could, might等可以用来表示推测和判断。具体用法如下:
1.must:must意为“一定;准是”。表示说话人对事物的推测可能性的程度非常大。
①“must be +表语”意为“一定……”,表示对现在情况的推测。
eg: I can’t understand them. They must be foreigners.表示推测的情态动词
4. ②“must be+现在分词”意为“一定正在……”,表示对说话瞬间情况的推测。
eg: She must be cooking now because I can smell something delicious.
③“must have +过去分词”意为“一定已经……”,表示对过去情况的推测。
eg: I can’t find my keys .I must have left them at home.
5. 2.may: may表示推测,语气没有表示推测的must语气强,意为“也许”,may not,意为“也许不”。
常见句型为:“may be +表语”意为“有可能……”,表示对现在的可能推测。
eg: He may be angry because he looks unhappy.
6. 3.can: can表示推测时,常用于否定句、疑问句中,can’t意为“不可能;应该不是”。
常用句型为:“can/can’t be +表语”意为“(不)可能……”,表示对现在情况的推测。
eg: That can’t be Maria, because she’s in hospital.
There’s someone outside. Who can it be?
7. 4.could/might:如果表示推测的把握性不是很大时,用could或might。它们常用于肯定句或疑问句中,意为“也许;可能”。
eg: He might be doing his homework now.
Could the news be true?
8. 1.—Excuse me, whose book is this?
—It__be John’s. It has his name on it.
A. must B. need C. can’t D.could
2.The man____be my English teacher. He has gone to Canada.
A. might B. must C. can’t D.can
3.After a long walk, the old man__be tired now.
A. can’t B. must C. has to D. need一、单项选择。APracticeCB
9. 4.—I think the girl under the tree must be Alice.
—No, it__be her. She’s in the gym now.
A.can’t B.mustn’t C.may D.must
5.Martin__get here in time, but I am not sure.
A.must B.might C.can D.shouldAB
13. Inference (推断)Reasonparents (impossible)being at homethief (impossible)being afraidneighbor (possible)wanting some helpaunt (certainly)coming to visit usThere is a loud knock at the door…
17. 经典示范 There is a loud knock at the door. The knock wakes me up. Who is it? It can’t be my father or mother, because they are both staying at home. It can’t be a thief. The thief is afraid,and it’s impossible for him to knock at the door. It may be my neighbor. Maybe he wants some help. Oh, it must be my aunt. She often comes to visit us on Sunday.