Grammar: Mood & Subjunctive Mood (3)
语法：语气和虚拟语气(3)

2．5 省去从句或主句的虚拟语气：虚拟结构中的从句或主句有时形式上可以省去，但意义上仍存在。

1）省去了条件从句的虚拟结构
That would be fine. (省略了if you should do it)
I wouldn't have done that. (省略了if I had been given the chance)

2）省去了结果主句的虚拟结构（常表示愿望）
If only I could help you!
If only he hadn't left.

2．6 虚拟语气的特殊用法

1) 在It is necessary (important, strange, impossible, impractical,advisable, natural … 等表示主观看法的形容词) that …这类句型里, that 引导的从句里，谓语动词用should + 动词原形，should 常省略。
It is advisable that he travel abroad.
It was necessary that the question be settled at once.
It was strange that he should have gone away without telling us.

2) 虚拟语气用在宾语从句中。
a. 用于动词wish后的宾语从句中，表示不可实现的愿望，或对过去事情的遗憾。
I wish I hadn't been so forgetful. Then I wouldn't have missed the wonderful lecture.
I wish I knew how to design a robot, but I don't.
I wish I hadn't said that.

b. 用于动词demand, require, suggest, propose, order, command, insist, urge, advise, desire等带起的宾语从句中，从句用should + 动词原形。should常省略。
Most students insist that the English teacher speak English either inside or outside the classroom.
My friend suggested that I should go to the theater for a rest.
Many parents urged that educational TV programs be manufactured for children.

* 这类动词的名词的定语从句也要相应地用虚拟语气should + 动词原形。should常省略。

The doctor's suggestion that he be operated on has been finally accepted by his family.
Everyone supports his insistence that smoking be prohibited in school.

c. It is time (that)…句型中。从句的谓语动词用动词过去时表示虚拟。意思是"早该干……"
It is time we went to school.
It is high time that we made up the missed class.

d. would rather / had better / would sooner等词或短语后面的从句中，谓语用虚拟语气，用动词一般过去时。
I'd rather that you left tomorrow.
I would much rather it was forgetten.

3) 虚拟语气用于 as if / as though 引导的状语从句中，表示和现在、过去或将来的事实不相符。
He talked about the moon as if he had been there.
She stood up as if by doing so she could have corrected everything.
She treats the old man kindly as though he were her father.

4) 用于特殊连词for fear that, lest, in case带起的从句，其虚拟语气形式是should + 动词原形，should常省略。
We dare not play jokes on Miss Liu lest she should be angry.
He works hard for fear that he fail the exam.
She speaks in a low voice in case she waken the baby.

5) 用于介词短语表示的虚拟。此类介词有 but for, otherwise, without, with, under more favorable condition, in case of …等。
He worked hard; otherwise he might have failed.
But for his help, I should not have succeeded.
Without you, things would be better.