1. 当permission 表示“允许，许可，同意”时，它通常是不可数的。如：

You have my permission to leave.

He had permission to go out for an hour.

No one is to leave this building without the permission of the police.

Students may not stay out after midnight without written permission.

2. 注意以下与动词的常用搭配：

(1) 表示请求某人允许自己做某事，通常连用动词 ask, ask for, request, seek 等：

She asked for permission to leave work early.

(2) 表示获得允许做某事，通常连用动词 gain, get, obtain, receive 等：

We have gained permission from the directors to use some of our funds.

(3) 表示允许某人做某事，通常连用动词 give, grant 等：

Who gave you permission to come in here?

(4) 表示不允许某人做某事，通常连用动词deny, refuse等：

Father denied me permission to use his car.

3. permission 前一般不用定冠词，但根据需要有时可用物主代词或名词所有格。例如：

She asked Mike’s permission to use his car.

如果表达的意思足够明确，也可省去物主代词：

I gave him (my) permission to leave.

注：表示允许做某事，其后通常接不定式作定语，且其中的不定式习惯上不能换成 of/for doing sth。