英文语法杂谈(2)：助动词
助动词的相关语法（auxiliary verb）
一、MIGHT
1.1 表示可能性（Possibility）：
It might rain today.
They might go to the cinema.
They might not go to the cinema.
We might go to dinner tonight, I'm not sure.
It might rain tomorrow.
He might not go to Japan next year.
You might shoot another panther this year.
1.2 其他用法：
You might post this for me.（请求）请你把这信寄一寄。
You might at least apologize. （责备）你至少该赔个不是。
He might at least have offered to help me.（责怪）他至少该说来帮助我。
I might have been a rich man.（懊悔）我该做到富翁了。
二、CAN
2.1 表示有能力：
Sam can play the guitar.
Can Howard sing?
He can't (cannot) understand German.
2.2 表示许可：
Can I park my car here?
No, you can't, it is a no parking zone.
Can I go to the theatre with Zhang?
2.3 表示可能：
A car can be a useful means of transport or a dangerous weapon.
She can be very hard to understand sometimes.
We can live life with a positive or a negative attitude.
2.4 在否定或疑问时，有“何至于”，“不可能”之意：
He cannot be a cruel man. 他不可能是一个冷酷的人。
Can they have said such a thing? 他们何至于说出这样的话？
三、COULD
3.1 作为can 的过去式：
She couldn't (could not) come to dinner last night.
They could walk faster when they were younger.
Sam could play the piano when he was a boy.
3.2 客气请求：
Could you tell me the time, please?
Could you help me, please?
Could I have a coffee, please?
Could we come and visit you this evening?
3.3 could not help-ing, could not but 有“不禁”，“忍不住”之意：
We could not but laugh. 我们忍不住发笑了。
We could not help laughing. 我们不禁笑了起来。
四、MUST
1、表示“必须”：
You must listen to him. 你必须听他的话。
(注意：如果要说“你不必听他的话。”可不能说“You must not liston