can(could) 和 may(might)

sentence:
Do I have to/Do me a favor?/To be careful/Any thing else?
I'm his fan/I'm his age/No one knows/Never mind/Count me on
That's neat/What's news?/Time is up/Is it yours?/Feel better?
She turns me off./It drives me crazy..

key words and expressions:
exclaim 呼喊,惊叫 sooner or later 迟早
go off 爆炸,出去,离去 at any moment 任何时候
sell out 卖完,出卖 sell up 变卖,为还债而变卖
as well 还是..好 may as well 最好,还是..好
neat 整洁的,灵巧的 get the better of 打败,智胜
sadly 沮丧地,悲痛地 prefer 更喜欢,宁愿
get the better end of 占上风,对...占上风,对...处于领先(有利)地位
rather 宁愿,宁可 pity 令人遗憾的

Pattern:
The bomb may go off at any moment.
What r u in a hurry for?
He sold his watch at a low price(for 300 pounds).
I have a meeting for 2 o'clock.
John sold up and went to Australia.

Syntax:
情态动词 can(could)/may(might) 表示可能发生,不确定的推测
could 比 can 更加委婉
might 比 may 更加委婉,更加不确定
Such things may(can) happen.
This may not(cannot) be true.
There is nothing to do now,so I might(may) as well go to bed.
Since u will know it sooner or later,I might as well tell u now.