虚拟语气中be为什么要用were（虚拟语气---Were-型虚拟式）

Were-型虚拟式只有一种形式，即不管主语是什么人称，动词一律用were,如 i were ,you were ,he were .

1：用于某些状语分句中

were-型虚拟式常用于由 if , if only ,as if ,as though,though 引导的条件状语和让步状语分句中，表示非真实的条件或让步。

eg:

If i were you ,i should wait till next week .

If it were to rain, the game would be put off.

If only i were not so nervous.

He spoke to me as if i were deaf.

He behaves as though he were better than us.

Though the whole world were against me ,i would do what i consider as right .

2:用于某些名词性分句中

were-型虚拟式常用于 wish, would rather ,suppose , imagine 之后的that-分句中，表示一种臆想的（通常是不可能发生的）情况。

eg:

I wish it were spring all the year round.

I'd rather i were not at the site of the accident.

Suppose the earth were flat .

Just imagine everyone were to give up smoking .

3:用动词的过去时形式表示假设意义

a:It is time that ....

It is time we went to bed .

You've been working hard.It's time you took a rest.

It is time we had dinner.

It is about time you made up your mind .(你该拿定主意了）

It is high time you lent her a hand .(你该帮她一把了）

b:I would rather / sooner (that )you /he /they....

I'm told they are going bu bus , but i would rather they went by train.

(......我倒宁愿他们乘火车去）

She will get home at dinner time ,but i would rather she got home a little earlier.

(........我倒希望她早点到家）

I'm sure he is keeping somethinf back .i'd rather he told me the truth.

(我肯定他有事瞒着我。我宁愿他对我讲真话）

c:if only....

If only i knew her address. (我要是知道她的地址就好了）

If only i had enough money with me .

If only he didn't drive so fast.

If only i had gone by taxi .(我要是打的去就好了）

d：He behaves as if /as though....

He behaves as if he owned this place.

他指手画脚，好像是这地方主人似的。

He ordered me about as if he was /were my boss.

他对我呼来喊去，好像是我老板似的。

They are staring at me as if i was /were crazy.

e: I wish (that)....

I wish i didn't have to go to work today.

我今天要能不上班就好了

I wish i was /were a bit taller .

我的个子要能高一点就好了

I wish i had brought a map with me .

我要是带了地图就好了

以上都表示与现在事实过过去事实相反的主观愿望。如果要表示对将来时态的主观愿望，通常用某些情态动词的过去时形式，此种结构便接近于客气的请求或委婉的劝告。

eg:

I wish you wouldn't smoke in public places.

I wish you would listen to your teacher's advice .

I wish i could do something for you in return .

I wish 与 i hope 都表示希望，但 i hope (that)...并不表示假设意义，随后的动词形式除表示委婉口气外，很少用过去时形式。

eg:

I hope you are ready.

I hope you're coming to our party.

I hope you can do something to help her .

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