could
[kJd]
v.
动词 can 的过去式
I could run faster then.
我那时能跑得更快一些.
（表示与事实相反的设想）能；可以
I could come tomorrow if you like.
如果你愿意,明天我可以来.
（委婉语）能
Could you do sth.for me?
你能替我做件事情吗?
应该
You could at least have met me at the station.
你至少应该到车站来接我.
可能
I wrote down the number so that I could remember it.
我写下了号码,那样我就能记住它了.
could
[kud]
v.,aux.
[can的过去式]
〔常用于从句中〕（过去、当时）能够,得以
〔用于虚拟语气中,表示相反的假设〕能,本来可以
〔表示可能性〕能,可能,可以
〔用于委婉语气〕能,可以
We could see the oil bleeding out from the joint.
(那时)我们可以看出油从接缝处渗出.
It was so dark that we could see nothing.
天太暗了,我们什么也看不见.
If I could go with you,I should feel very glad.
假如我能同你们一起去,我会感到非常高兴.
You could have been more considerate.
你本来可以更慎重些.
If you tried,you could do the work better.
如果你试试的话,准能把那项工作干得更好.
C-I borrow your thermos?
我可以借用你的暖水瓶吗?
xiguanyongyu:could not (help)but
不能不
who could have
谁〔没人〕会
nobody could have
谁〔没人〕会