整理了小升初英語語法大全：如何表達本來該做某事?，快來看看吧！希望能幫助到你~更多相關(guān)訊息請關(guān)注！
should have done
“should have + 動詞的完成式”表示本應該做而實際上沒有做，它的否定形式表示某種行為本不該發(fā)生但卻發(fā)生了。有責備的意味。
You should have started earlier, but you didn't.
你本應該早點兒出發(fā)，但是你沒有。
You should have washed the wound.
你應該已經(jīng)洗好了傷口。
She shouldn't have taken away my dictionary, for I wanted to use it.
她本不應該拿走我的詞典，因為我要用它。
You shouldn't have been so rude to him.
你本不應該對他那么粗魯。
注：“should have + 完成式”雖然可以表猜測，但因為會造成歧義，應少用。
ought to have done
1、“ought to have + 動詞的完成式”表示過去應做某事而實際未做，它的否定形式表示本不應該做某事卻做了(用法和should相同)。
You ought to have helped him, but you didn't.
你本應該幫助他但你沒有。
You ought to have studied harder.
你本應該更努力學習的。
He ought not to have stopped his work halfway.
他本不應該做這項工作時半途而廢。
He oughtn't to have done that.
他本來就不該做那件事。
2、“ought to have + 動詞的完成式”還可以用來表猜測。
They ought to have arrived by now.
現(xiàn)在他們想必已經(jīng)到達。
If he had started at nine o'clock, he ought to have been in London by eleven o'clock.
如果他在九點出發(fā)，那他十一點鐘該到達倫敦了。
小升初英語語法零基礎：may have done用法小結(jié)
may/might have done 推測過去
“may/might+動詞的完成式”表示對過去發(fā)生的行為的推測。例如：
-Whatever has happened to George?
-喬治發(fā)生了什么事?
-I don't know. He may have got lost.
-我不知道，他可能迷路了。
You might have read about it in the papers.
你可能在報上已經(jīng)看過這個消息了。
(之前我們做過can have done用法小結(jié)，can have done表推測時都是對過去進行推測，但是may have done不僅可以推測過去)
may/might have done 推測現(xiàn)在
“may/might+動詞的完成式”表示對現(xiàn)在情況的推測。例如：
She might have got up now.
現(xiàn)在她可能已經(jīng)起床了。
may/might have done 預測未來
“may/might+動詞的完成式”表示推測將來某時之前的情況。例如：
He may have left when you get there.
等你到達的時候他可能已經(jīng)離開了。
注意：may have done 和 might have done 表推測時，might 所表示的可能性比 may 小，語氣較委婉：
How quickly time passed! It might have happened yesterday.
時間過得好快啊!這事好像就發(fā)生在昨天。
He might have seen the surprise in my face.
他或許已經(jīng)看到了我驚異的表情。
might have done 表輕微責備
might have done 除了能夠表推測，還能表示過去本來可以做而實際并沒有做。這時帶有輕微的責備之意。例如：
The proposal might have been refused.
這個建議本該拒絕的。(有輕微的責備之意)
I might have taken another path.
我本可以走另一條路。
may not/mightn't have done 表“可能不”
之前我們講到過 can't/couldn't have done 是表示“不可能”，而 may not/mightn't have done 則是表示“可能不”，要注意區(qū)分哦：
He can't have been at the meeting, he's on a business trip this week.
他不可能有出席會議，他這周出公差。
We couldn't have done it without you.
沒有你我們肯定完成不了。
They may not have known it beforehand.
他們事先可能不知道這事兒。
They mightn't have regarded me as their friend.
他們可能沒有把我當作朋友看待。
should have done
“should have + 動詞的完成式”表示本應該做而實際上沒有做，它的否定形式表示某種行為本不該發(fā)生但卻發(fā)生了。有責備的意味。
You should have started earlier, but you didn't.
你本應該早點兒出發(fā)，但是你沒有。
You should have washed the wound.
你應該已經(jīng)洗好了傷口。
She shouldn't have taken away my dictionary, for I wanted to use it.
她本不應該拿走我的詞典，因為我要用它。
You shouldn't have been so rude to him.
你本不應該對他那么粗魯。
注：“should have + 完成式”雖然可以表猜測，但因為會造成歧義，應少用。
ought to have done
1、“ought to have + 動詞的完成式”表示過去應做某事而實際未做，它的否定形式表示本不應該做某事卻做了(用法和should相同)。
You ought to have helped him, but you didn't.
你本應該幫助他但你沒有。
You ought to have studied harder.
你本應該更努力學習的。
He ought not to have stopped his work halfway.
他本不應該做這項工作時半途而廢。
He oughtn't to have done that.
他本來就不該做那件事。
2、“ought to have + 動詞的完成式”還可以用來表猜測。
They ought to have arrived by now.
現(xiàn)在他們想必已經(jīng)到達。
If he had started at nine o'clock, he ought to have been in London by eleven o'clock.
如果他在九點出發(fā)，那他十一點鐘該到達倫敦了。
小升初英語語法零基礎：may have done用法小結(jié)
may/might have done 推測過去
“may/might+動詞的完成式”表示對過去發(fā)生的行為的推測。例如：
-Whatever has happened to George?
-喬治發(fā)生了什么事?
-I don't know. He may have got lost.
-我不知道，他可能迷路了。
You might have read about it in the papers.
你可能在報上已經(jīng)看過這個消息了。
(之前我們做過can have done用法小結(jié)，can have done表推測時都是對過去進行推測，但是may have done不僅可以推測過去)
may/might have done 推測現(xiàn)在
“may/might+動詞的完成式”表示對現(xiàn)在情況的推測。例如：
She might have got up now.
現(xiàn)在她可能已經(jīng)起床了。
may/might have done 預測未來
“may/might+動詞的完成式”表示推測將來某時之前的情況。例如：
He may have left when you get there.
等你到達的時候他可能已經(jīng)離開了。
注意：may have done 和 might have done 表推測時，might 所表示的可能性比 may 小，語氣較委婉：
How quickly time passed! It might have happened yesterday.
時間過得好快啊!這事好像就發(fā)生在昨天。
He might have seen the surprise in my face.
他或許已經(jīng)看到了我驚異的表情。
might have done 表輕微責備
might have done 除了能夠表推測，還能表示過去本來可以做而實際并沒有做。這時帶有輕微的責備之意。例如：
The proposal might have been refused.
這個建議本該拒絕的。(有輕微的責備之意)
I might have taken another path.
我本可以走另一條路。
may not/mightn't have done 表“可能不”
之前我們講到過 can't/couldn't have done 是表示“不可能”，而 may not/mightn't have done 則是表示“可能不”，要注意區(qū)分哦：
He can't have been at the meeting, he's on a business trip this week.
他不可能有出席會議，他這周出公差。
We couldn't have done it without you.
沒有你我們肯定完成不了。
They may not have known it beforehand.
他們事先可能不知道這事兒。
They mightn't have regarded me as their friend.
他們可能沒有把我當作朋友看待。