ability

能力，才能，才智

前面讲过 can 可以表示能力：

I can drive = I know how to drive

Can 的语法规则：

I can drive.

You can drive.

He can drive.

She can drive.

We can drive.

They can drive.

否定形式是 cannot 或 can't：

*在正式语境或强调时用 cannot，一般就用 can't。

I cannot / can't drive.

You can't drive.

He can't drive.

……

疑问句把 can 放到主语前面：

Can you drive?

Can he drive?

……

简短回答：

Yes I can. / No I can't.

Yes he can. / No he can't.

小对话

A: Can she drive?

B: Yes she can. / No she can't.

Can 的过去式：

是 could，表示过去具备某个能力。

I could run fast when I was a child.

我小时候跑得很快。

否定形式是 couldn't：

I couldn't speak a foreign language when I was a child.

我小时候不会说外语。

foreign language 外语

foreign 外国的

language 语言