As it is， we can not help him.

As it was， we could not help him.

（2）用于句末

Let‘s keep it as it is.

You mustn’t go to the ball as you are.你不能这样去参加舞会。

有时it可以省略为“as is ”，意即：照现在的样子，常指“不再修理或改进”等情况。

He has an old radio as is.他有一台没有修理过的旧收音机。

I‘ll sell it to you as is， but don’t complain if it doesn‘t work.

（3）句中时，用逗号把它从前后隔开

A.虚拟语气句式+but +as it is / was，该结构意为：其实;事实上

I thought things would get better， but as it is， they are getting worse and worse.

The rice could have been got in yesterdy if the weather had been fine， but as it was， it had to be left in the fields.

B.过去分词+as it is，表示强调前面的过去分词

Written as it is in an interesting way， this book is enjoyable to young and old alike.

Published as it was at such a time， his work attrached much attention.

C.现在分词+ as it does（did）。意为：因为这样，（实际）所以……

Living as he does in Shanghai， he knows the place extremely well.

Reading as he did many times， he could recite it fluently.

几个类似的结构：

A. as it stands 根据目前情况来看

As it stands， it is certain that our country can realize the four modernization ahead of schedule.

B. such as it is不怎么样，质量不过如此

The room， such as it is， is very bright.

C. as it were =as if it were so.属虚拟语气，用于插入语。不可以与as it is 混淆

He is ， as it were， a living dictionary.

Comrade Lei Feng still lives， as it were ， in our heart.

4.have + the + 抽象名词 +不定式

I had the fortune to succeed.我很幸运获得了成功。

have = possess原来指肉体和精神上的特征，现作为一种天赋而具有的。

She had the cheek （ = impudence） to say such a thing. = She was so impudent as to say such a thing.她厚颜无耻地说出这样的话。

How can you have the heart （ = hard-heartness） to drown such darling little kittens？

你何忍心把如此可爱的小猫淹死？