...his work; otherwise, he wouldn’t be enjoying himself by the se...

A 试题分析： 句意：他一定是完成了他的工作，否则他不会在海边玩得那么开心。A. must have completed对过去的肯定推测；B. should have completed本应该完成，实际上没完成；C. ought to complete应该完成；D. must complete必须完成。表示对现在的推测。故选A。考点: 考查情态动词表推测的用法。

根据He wouldn’t be enjoying …推断，他一定完成了工作。should have done表示“（过去）该做某事而没有做”；wouldn’t have done表示“（过去）实际上做了某事”； can’t have done表示对于过去动作否定的推断，意为“（过去）不可能做了某事”。故答案为A.

句意为：他一定是已完成工作了；否则，他就不会在海边玩得那么高兴了．由此可知是对过去发生的事情的肯定推测，故用must．

5. He ___ have completed his work; otherwise, he wouldn't be enjoying himself by the seaside. (05 北京卷)A. should B. must C. wouldn't D. can't 答案为 B。用法同4题。句意：他肯定做完了工作，不然他就不会在海边痛快地玩儿了。6. — Do you know where David is? I co...

5. He ___ have completed his work; otherwise, he wouldn't be enjoying himself by the seaside. (05 北京卷)A. should B. must C. wouldn't D. can't 答案为 B。用法同4题。句意：他肯定做完了工作，不然他就不会在海边痛快地玩儿了。6. — Do you know where David is? I co...

5. He ___ have completed his work; otherwise, he wouldn't be enjoying himself by the seaside. (05 北京卷)A. should B. must C. wouldn't D. can't 答案为 B。用法同4题。句意：他肯定做完了工作，不然他就不会在海边痛快地玩儿了。6. — Do you know where David is? I co...

5. He ___ have completed his work; otherwise, he wouldn't be enjoying himself by the seaside. (05 北京卷)A. should B. must C. wouldn't D. can't 答案为 B。用法同4题。句意：他肯定做完了工作，不然他就不会在海边痛快地玩儿了。6. — Do you know where David is? I co...

1、can have done 和could have done 的区别 can have done是表示应该做某事而没有做,所以既然知道没有做,那肯定是已经发生了。could have done 表示本能做而实际未做,是虚拟语气.2、can't have done和couldn't have done的区别 can't have done（不可能做过）是must have done（一定做过）的...

"I don't know how fast I can go. I'm not really worried about that," he said. "I'm just looking forward to going on and doing better things. I hope to improve every year. "I'll definitely be going to the London Olympics to defend my title." Bolt said his win in the 200m,...