一.一般虚拟的构成：(省略if, 要将should/were/had 提到句首)
(1). 对现在的虚拟：If +S.+ did/were sth., S.+ would/could/should +do
If I had time, I would attend the meeting.
If I were you, I would seize the chance to go abroad.
(2) 对过去的虚拟：If +S.+had + p.p, S.+ would/could/should have + p.p
If you had taken my advice, you would not have failed in the exam.
If + S. + did/were/should do/were to do, S + would/should/could do sth.
If you came tomorrow, we would have the meeting.
If it were to rain tomorrow, the sports meeting would be put off.
If he should not come tomorrow, we should put off the meeting till next day.
注意：Had we made good preparations, we might have succeeded.
Had it not rained, we would have gone out for a walk.
Were I you, I would not do such a thing.
(1) 不同时间的虚拟：If he had listened to me, he would not be in trouble now.
If he had told me yesterday, I should know what to do now.
He could have passed the exam, but he wasn’t careful enough.
You should have come earlier, the bus left a moment ago.
(1).suggest, advise, recommend, propose, order, command, request, require, demand + that –clause (should do/do )
He suggested that we (should) save money for the future.(insist的判断)
(2) It is suggested/advised/ordered/requested/required that –clause(should do/do)(主语从句)
(3) My advice/suggestion/request/requirement is that-clause (should do /do) (表语从句)
His suggestion/advice/request/requirement that –clause(should do/do ) is.. (同位语从句)
(4) It is natural/necessary/strange that-clause (should do/do)表惊奇、怀疑、惋惜、不满、理应如此等。
It’s strange that he should have missed the train. (表竟然)
It is important that we should learn from others.(表理应如此)
It is a pity that he should not go with us.(表惊讶、不满)
(5)wish + that clause (did/were 与现在相反)
wish + that clause (would/could/might + do与将来相反)
wish + that clause ( had done 与过去相反)
I wish I could go with them tomorrow.
I wish I had never met him.
(6) It is (high/about) time + clause (did, should do )
It is (high/about) time we went home.
(7) would rather + clause (did 与现在或将来相反);(had done 与过去相反)
I would rather you came tomorrow. I would rather you hadn’t told her the news.
(8) If only + clause ( did/were与现在相反) ((would/could/might + do与将来相反)
( had done 与过去相反) “要是。。。就好了“
If only he would come tomorrow! If only I had taken her advice!
If only I were ten years younger!
(9) as if + clause (did/were 与现在相反) (would/could/might + do与将来相反)
( had done 与过去相反)
She treats Kate as if she were her own daughter.
They talked as if they had been friends for years.
(10) would like/was/were to have done something
I would like to have attended the party, but one of my friends came to see me.
(11) without/but for + n.= if it were not for +n./if it hadn’t been for + n. (otherwise后从句同)
I would not have passed the exam without your help.(=if it hadn’t been for your help)