①could have done表示对过去所发生事情的推测,一般用于否定句和疑问句。 He couldn't have left for Beijing, for I saw him just now.他不可能去北京了,因为我刚才看见他了。 Could he have told his mother the truth?他会把真相告诉他母亲吗? ②could have done本...
⒋ Could/can+have done 结构表示对过去发生的事情的“怀疑”或“不肯定”。could 加完成式还用于肯定句时一般表过去可能完成而却未完成的动作。 如:Can they have won the basketball ...
—— Could I have the television on? —— Yes, you can. / No, you can’t. 2)在否定,疑问句中表示推测或怀疑。 He couldn’t be a bad man. 他不大可能是坏人。 比较may和might 1) 表示允许或请求;表示没有把握的推测;may 放在句首,表示祝愿。
C. supposing to have been written D. supposing to be written 4. The money with which you were to buy dog food is gone, but Spot looks so hungry! 让你们用来买狗食的钱已经花光了,可是斑点看上去还是这么饿! “be + 不定式”结构 (1) 表示“将来的安排,将来...
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