couldaux.可以;能;可能;can的过去式
could well可以, 很可以
Could be.(回答用语)可能如此
could affordconj.有钱购买(有能力负担;花得起)
couldnot helpconj.不禁(不得不)
couldn't help从 ... 的角度; 从 ... 的观点
could not but不得不 ...
could do withadj.将就(希望得到;需要;可利用;满足于)
could as well不妨, 还不如, 最好
could not help不得不, 禁不住
Could I go?在非常时刻