could
1)提出委婉的请求,(注意在回答中不可用could).
--- Could I have the television on?
--- Yes, you can. / No, you can't.
2)在否定,疑问句中表示推测或怀疑.
He couldn't be a bad man.
他不大可能是坏人.
could
1)提出委婉的请求,(注意在回答中不可用could).
--- Could I have the television on?
--- Yes, you can. / No, you can't.
2)在否定,疑问句中表示推测或怀疑.
He couldn't be a bad man.
他不大可能是坏人.