应对情态动词考题的三个小技巧
(2) This cake is very sweet. You _________ a lot of sugar in it.
A. should put B. could have put C. might put D. must have put
分析:答案选D。前文说“蛋糕很甜”,下文的语境显然应该是“你一定是在里面放了很多糖”,故用“must+完成式”表示对过去情况的肯定推测。
(3) —The woman biologist stayed in Africa studying wild animals for 13 years before she returned.
— Oh, dear! She _________ a lot of difficulties!
A. may go through B. might go through
C. ought to have gone through D. must have gone through
分析:答案选D。由上文的stayed可知,此题是对过去情况有把握的肯定推测。句意为“那个女生物学家呆在非洲研究野生动物13年才回来。”“天啊!她一定经历了不少苦难!”
技巧3 注意分清适用句型
即要分清所考查的情态动词是用于肯定句型,还是用于疑问句型或否定句型,同时还要注意情态动词在某些特殊情况下所使用的特殊句型。如:
The World Wide Web is sometimes jokingly called the World Wide Wait because it _________be very slow.
A. should B. must C. will D. can
分析:答案选 D。在通常情况下,情态动词 can 表示推测时,只用于否定句和疑问句,不用于肯定句,但有一种特殊情况就是它可以用于肯定句中表理论上的推测或表示“有时”之意,而此题考查的正是can 表示“有时”的用法。