couldn`t的意思和时态
couldn`t的意思和时态
can't help but do 和couldn't help but do 只是时态的区别吗?
couldn't get through.中through的意思,和词性.
didn't 和couldn't的区别,
couldn't放句首有难道的意思吗
couldn‘t什么意思?
could和couldn't的不同
couldn t和
can't和couldn't
完成时态的用法mary couldn't have received my letter,or she have rep
may not/can't/couldn't/needn't/mustn't举例区别意思和用法
couldn't和shouldn't的区别,急要