can/ kæn /

1.aux vb
(be able to) 能

can I help you?
您要买点儿什么?
2.aux vb
(in general) 我能帮你吗?

you can do it if you try
如果试试的话你是能做的
I can't hear/see anything
我什么也听/看不见
I can't remember
我不记得了
she can't sleep
她不能入睡
you can always try telephoning him at home
你可以试着往他家里打电话
as you can imagine...
就如你能想像的那样…
how can I ever thank you?
我该怎么谢你才好呢?
I can't understand why...
我不能理解为什么…
3.aux vb
(know how to) 会

I can swim/drive
我会游泳/开车
can you play a musical instrument?
你会一种乐器吗?
4.aux vb
(permission,requests) 可以

can I use your phone?
我可以用你的电话吗?
can you help me?
你可以帮我一下吗?
can't you leave me alone?
你就不能让我单独呆一会儿吗?
this cannot be allowed to continue
不能再这样下去了
5.aux vb
it can't be true! (disbelief,puzzlement) 这不可能是真的!

you can't be serious!
你不是认真的吧!
it can't have been them!
不可能是他们!
what can he want?
他究竟想要什么?
6.aux vb
(possibility) 可能

the illness can last for up to six months
病情可能持续近6个月
he can be very unpleasant
他有时会非常不高兴
can she have finished already?
她有可能已经完成了吗?
how can millions of dollars disappear?
成百万的美金怎么可能消失呢?