their wages (should) be raised by 10 per cent.
The teacher decided that you do the experiment first.
5. 某些名词后的表语从句和同位语从句中谓语动词要用虚拟语气
在一些名词后面的表语从句和同位语从句中,谓语动词要用虚拟语气。这时,谓语动词用动词原形或should +动词原形。这类名词一般表示命令,要求,决定,建议,主张等概念,主要有:advice, idea, instruction, motion, order, plan, proposal, recommendation, request, requirement, suggestion,等。
My suggestion is that we (should) send for a doctor immediately.
He gave the order that they (should) do the experiment again.
6. 错综时间条件句
条件从句表示的动作和主句表示的动作,有时发生的时间是不一致的。如从句是对过去情况的假设,而主句可能是对现在正在进行情况的假设。 这种句子称为错综时间条件句。
If the weather had been more favourable, the crops would be growing still better.
7. 某些主语从句中的谓语动词要用虚拟语气
某些表示命令,要求,决定,建议,主张以及“重要性”和“紧迫性”等概念的主语从句中谓语动词要用虚拟语气。这时,谓语动词用动词原形或should +动词原形。这类主语从句一般由 “It is (was) + 形容词/过去分词 + that引导的从句”构成。该结构中,常用的形容词主要有:advisable, appropriate, desirable, essential, imperative, important, necessary, obligatory, proper, urgent, vital等;常用的过去分词主要有:arranged, decided, demanded, desired, ordered, proposed, recommended, requested, suggested等。
It is necessary that you (should) stop smoking so heavily.
It is arranged that you (should) enter for this competition.
8. as if / though引起的从句
当as if / though引起的从句所表达的内容完全与实际情况相反或者纯粹是一种假设时,通常要用虚拟语气。如果从句表示与现在的事实相反,谓语动词用一般过去时;如果从句表示与过去的事实相反,谓语动词用过去完成时;如果从句表示与将来的事实相反,谓语动词用would (might, could) + 动词原形;
They talked as if they had been friends for years.
I remember the whole thing as if it happened yesterday.
It looks as if it might rain.
Note: 如果as if / though引起的从句所表达的内容被看作是事实或者有可能是真实的,则要用陈述语气。
It seems as if it is going to rain.
The meat tastes as if it has already gone bad.