UKiset语法学习中的盲区

　　UKiset考试是专门面向想要进入英国中小学留学而设计的考试，所以近几年逐渐成为国内家庭关注的重点，考试内容包括听力、口语、阅读等等，虽然语法没有专门的考试，但却无处不在，所以重要性可见一斑，今天我们就来说说UKiset语法学习中的一些盲区！

　　1) could have + 过去分词

　　A. 表示对过去可能发生的事情的推测，意为，“可能做了某事”。

　　He couldn’t have seen her yesterday.

　　They could have lost their way.

　　B. 表示某事在过去本有可能发生，但事实上并未发生，意为，“本可以做某事”。

　　We could have started a little earlier.

　　I could have killed her. It was a narrow escape.

　　2) may (might) have + 过去分词

　　A. 表示对过去情况的推测，意为，“可能已做某事”。

　　He may have heard the news.

　　I might have come to a wrong conclusion.

　　B. 表示一种未实现的可能性，即本可以做某事，而实际上并没有做，有时含有抱怨的口吻。

　　It was a narrow escape. You might have killed yourself.

　　A lot of men died who might have been saved.

　　3) must have + 过去分词

　　表示逻辑上的必然性，即按照某些现象推断过去肯定发生过的某事。

　　She must have made a big mistake.

　　The city at one time must have been prosperous, for it enjoyed a high level of civilization.

　　4) needn’t have + 过去分词

　　表示过去不必做某事，但已经做了，即本可不必做某事。

　　You needn’t have woken me up. I don’t have to go to work today.

　　He needn’t have watered the flowers, for it is going to rain.

　　5) should / ought to have + 过去分词

　　表示过去应该做某事而实际上没有做。

　　You should / ought to have done what your parents told you. (But you failed to do it.)

　　You should / ought to have been more careful. (But you weren’t.)

　　6) shouldn’t / oughtn’t to have + 过去分词

　　表示过去不应该做某事而实际上却做了。

　　You shouldn’t / oughtn’t to have crossed the road when the lights were red. (But you did.)

　　They shouldn’t / oughtn’t to have left so soon. (But they did.)

　　7) would have + 过去分词

　　表示对现在或将来某时之前业已完成的动作的推测。可译为，“可能”、“也许”、“想必”。

　　He would have arrived by now.

　　She would have recovered by then.