虛擬語氣在從句中的運用
虛擬語氣在名詞性從句中的運用：
A）用于賓語從句中。
wish +從句，表示不可能實現(xiàn)的愿望。
wish that…had done…（過去）
wish that…did/were… （現(xiàn)在）
wish that… would/could do…（將來）
如：
We wish we had arrived there two hours earlier.
I wish I were a bird.
I wish you could come tomorrow.
用于表示建議、愿望、命令等詞后的賓語從句中，常見的動詞有：suggest, insist, command, advise, desire, order, request, require, demand that…(should) do…
例句：
We insisted that she (should) go with us.
He suggested that we (should) start off early the next day.
The doctor ordered that the patient ( should ) be sent to hospital without delay.
They insisted that the boy (should ) go with them.
注意：當suggest表示“暗示、表明”之意時，不用虛擬語氣，應用陳述語氣。如：
The smile on his face suggested that he was satisfied with out work.
當insist表示“堅持認為”之意時，不用虛擬語氣，應用陳述語氣。如：
The man insisted that he had never stolen the money.
在would rather, had better 后的賓語從句中，也用虛擬語氣，其構(gòu)成為動詞過去式。如：
I would rather they didn't hear of the news.
B) 用于主語從句中
It is desired /suggested /proposed/necessary/important/strange/natural/a pity + that 從句。從句中的謂語動詞用“should + 動詞原形”，should 可以省略。如：
It is suggested that the meeting should be put off till next week.
It is strange that he should have acted toward his parents like that.
注：以上句式也可以用陳述語氣。如：
It's strange that he didn't come yesterday.
It's a pity that you can't dance.
C) 用于表語從句和同位語從句中。
在suggestion, proposal, order, plan, idea, request, advice等名詞后的表語從句和同位語從句中要用虛擬語氣。其構(gòu)成是“should + 動詞原形”。如：
My idea is that we should think it over before accepting it.
We all agreed to his suggestion that we should go to Dalian for sightseeing.
三、虛擬語氣用在as if (as though), even if (even though)等引導的表語從句或狀語從句中。
表現(xiàn)在：用過去時；表過去：用過去完成時態(tài)；表將來：用過去將來時態(tài)。如：
He looks as if he were an artist.
She speaks English so fluently as if she had studied English in Ameirca.
Even if he were here, he could not solve the problem.
四、虛擬語氣用于定語從句中。
It is (high) time (that)……（此句型意為“現(xiàn)在該……”，用來表示提議）句型中，定語從句的謂語動詞用過去式，或should + 動詞原形（其中should 不能省略）。如：
It is (high) time that you went to school.
It is (high) time that we should start now.
五、用于if only 引導的感嘆句中。
If only I were a flying bird!
If only I had seen the film!
六、在含有If it were not for或If it had not been for條件句的虛擬語氣中。
If it were not for the rain, the crops would die.
If it had not been for your help, we couldn't have finished the work ahead of time.
七、用于表示委婉語氣的句型中。
It would be better for you not to do that.
Would you be so kind as to show me the way to the railway station?
Could you please help me with this heavy bag?
八、用于“may + 動詞原形”表示“祝愿……”，may 須置于句首。
May you succeed!
May you be happy!