1. that從句中:
1) wish, would rather (sooner), had better:
I wish I were as strong as you.
I wish I had paid more attention to our pronunciation.
I wish I remembered the address.
I would rather they came tomorrow (you had gone there too).
I had rather (that) you told him than I did.
2) suggest, order, demand, propose, command, request, desire, insist 等動詞后的賓語從句:
The commander ordered that all civilians (should) be evacuated.
He asked that he be given an opportunity to try.
She urged that he write and accept the post.
3) it is desired, it is suggested, it is requested, it was ordered, it was proposed, it is necessary, it is important, it has been decided 等結(jié)構(gòu)后的主語從句中.
It was arranged that they leave the following week
It will be better that we meet some other time.
4) suggestion, motion, proposal, order, recommendations, plan, idea等后面的表語從句和同位語從句:
His sole requirement is (was) that thy system be adjusted.
2. 在某些句型中
1) it is time that
It is time that we went (或should go) to bed.
It is high time we (should) put an end to this controversy.
2) as if (though) 引起的從句:
They talked (are talking) as if they had been friends for years.
It seems as if it was (were) spring today.
He acts (acted) as if (though) he were (was) an expert.
3) 以lest, for fear that 和 in case 引起的從句(這時謂語多用 should +動詞原形):
He took his raincoat with him lest it should rain.
He put his coat over the child for fear that (或lest) he should catch cold.
I’ll keep a seat for you in case you should need it.
4) 以whatever, whoever, no matter what這類代詞或詞組引起的從句(這時, 謂語多用may加動詞原形構(gòu)成):
Whatever defects he may have, he is an honest man.
Come what may, we will go ahead. 不管發(fā)生什么情況, 我們都要干下去.
I accept that he is old and frail; be that as it may, he’s still a good politician.
我承認他年老體衰, 然而盡管如此, 它仍是優(yōu)秀的政治家.
3. 條件句
1) 虛擬條件句主要有下面兩類:
a) 表示現(xiàn)在及將來情況(表示純?nèi)患僭O或?qū)崿F(xiàn)的可能性不大的情況):
謂語主要形式如下(be多用were這個形式):
從句 主句
過去式 would + 動詞原形
If I were you, I wouldn’t lose heart.
How nice it would be if you could stay a bit longer.
b) 表示過去情況的虛擬條件句(與事實完全相反的假設情況), 謂語主要形式如下:
從句 主句
had + 過去分詞 would have + 過去分詞
She would have come if we had invited her.
If I hadn’t taken your advice, I would have made a bad mistake,
You wouldn’t have caught cold if you had put on more clothes.
2) 有時候, 條件從句表示的動作和主句表示的動作, 發(fā)生的時間是不一致的(如一個是過去發(fā)生的, 一個是現(xiàn)在發(fā)生的). 這時, 動詞的形式要根據(jù)表示的時間來調(diào)整. 這種句子可以稱為錯綜時間條件句.
If he had received six more votes, he would be our chairman now.
If we hadn’t got everything ready by now, we should be having a terrible time tomorrow.
3) 有時假設的情況并不以條件從句表示, 而是通過一個介詞短語來表示.
Without music, the world would be a dull place.
We could have done better under more favorable conditions.
That would have been considered miraculous in the past.
But for the storm, we should have arrived earlier.
4) 如果條件句從句中包含有 were, had, should 或could, 有時可把if省略掉, 并把were, had, should或could放在主語前面.
Had we made adequate preparation, we might have succeeded.
Should there be a flood, what should we do?
Were it not for their assistance, we would be in serious difficulty.