mustn't have done和can't have done的区别最好有例子

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mustn''thavedone和can''thavedone的区别最好有例子mustn''thavedone和can''thavedone的区别最好有例子mustn''thavedone和can''thaved

mustn't have done和can't have done的区别最好有例子
mustn't have done和can't have done的区别
最好有例子

mustn't have done和can't have done的区别最好有例子
首先have done表示已经做过,这点就不用谈了.
can't have done 表示以前不可能做某事.
例句
---Where____Margaret have put the empty bottles?
---She________them away.They must be somewhere.
A.can;can't have thrown
B.must;must have thrown.
C.must;needn't
D.can;must throw
答案为A.第一个句子是一个疑问句而且表示可能性的推测,所以只能用情态动词can或could,第二句的答语表示对过去的推测,所以用can't have done.
请看常见的“情态动词 + have + 过去分词”的用法:
一、“must + have + 过去分词”表示对过去发生的事情或状态进行推测,语气比较坚定,通常只用于肯定句.如:
It must have rained last night,for the ground is wet.
You must have been mad to speak to the servant.
二、“can / could + have + 过去分词”表示对过去某种情况的怀疑或不确定.can和could一般用于否定句和疑问句,could的语气较can弱.如:
I didn't see her at the meeting this morning; she can't / couldn't have spoken at the meeting.
He can't have finished the work so soon.
三、“may / might + have + 过去分词”表示对已发生的动作或存在的状态进行不肯定的推测,might的语气比may弱一点.这种结构主要用于肯定句和否定句,疑问句改用can或could.如:
They may not have known it beforehand.
You might have read about it in the papers.
四、“need + have + 过去分词”表示过去做了不必做或不需要做的事情,或过去做某事纯属多余.如:
Need they have done it last week?
I needn't have bought so much wine—only five people came.
五、“should / ought to + have + 过去分词”表示过去本该做某事但没做,其否定式表示过去不该做某事但做了,这种句式含有不满或责备之意,ought to的语气比should强一些.如:
You ought to / should have studied harder.你本应该更努力学习的.(但没有)
He oughtn't to / shouldn't have done that.他本来就不该做那件事.(可是做了)
六、“would + have + 过去分词”表示对过去的某种情况进行猜测,或本来要做某事却因某种原因未做成,通常用来说明某一情况,但不像用should或ought to那样含有责备之意.如:
I guess the poet would have been about twenty when she wrote her first poem.
Another worker wouldn't have acted like that.

mustn't have done:……一定没做过某事
can't have done:……不可能做过某事

语气程度的区别,前者 过去一定没做某事

mustn't have done和can't have done的区别最好有例子 区别shouldn't have done 和 needn't have done Thanks.You ______ it.I could manage it myself A.needn’t doB.needn’t have done C.mus...Thanks.You ______ it.I could manage it myself A.needn’t doB.needn’t have done C.mustn’t do D.shouldn’t have done中B和D有什么区别?Catherine,I have I come all the way to say 3Q for your help and we ( )it without you.是情态动词+have done 为什么不可以添mustn‘t have done和shouldn't have done而必须添couldn’t have done 请问must的否定形式是不是不能表推测?有木有mustn't have done 滴形式?推测和虚拟是推测和虚拟到底是什神马?must have done 可以表推测,能表虚拟吗?偶乱了. 为什么是not have done和hadn't done ? 求两组英语句型的解释could have done 和 couldn't have doneshould have done 和 shouldn't have done should have done和shouldn't have done,couldn't have have to,has to,can和mustn't的区别 can’t +have done It was ,I should say,very kind of you to come all the way to help them,but you ___.A.didnt have to B.wouldnt have doneC.mustnt have done D.mightnt have done It was very kind of you to do the washing?up,but you _______ it.a、mustn’t have done b、 wouldn’t have donec、 mightn’t have done d、 didn’t have to do为什么? couldn't have done和mightn't have done有什么区别 shouldn't have done和wouldn't have done的意思 could't have done和can't have done的区别 can have done和could have done有无区别?can't have done和couldn't have done有无区别?如果有,区别是什么? must 和 have to 的异同?mustn't 和 don't have to 的异同? must 和 have to 有什么不一样?mustn't 和 don't have有什么不一样?