VOA慢速英语:Modals for Asking Permission

短语讲解：

1. The teacher was saying the student is able to leave the room, but does not have permission to do so.

be able to 能够; 能，会
例句：He will be able to take up his normal routine shortly.
他不久就能处理日常事务。

2. May is the most formal way to ask for permission.

ask for 请求…; 要求…; 找…; 自找麻烦
例句：He ask for leave of absence to visit his mother in hospital.
他请假去探望住院的母亲。

3. In addition to expressing permission, may also expresses possibility. For example, “It may rain” means that there is a possibility of rain.

in addition to 除…之外
例句：In addition to light, there are dangerous radiations gi-ven off by the sun.
除了光以外，太阳还发出危险的放射线。

4. Could is used with any subject to ask for permission.

ask for 请求…; 要求…; 找…; 自找麻烦
例句：He ask for leave of absence to visit his mother in hospital.
他请假去探望住院的母亲。

5. Be careful with may.

be careful with 照顾，对…过细地
例句：Be careful with the dynamite.
当心这炸药。