Iisten!Helen is singing in the next room.It ( ) be Helen.She has _英语解答

Iisten!Helen is singing in the next room.It ( ) be Helen.She has gone to Beijing.A.mustn't B.can't
请说说musn't与can't的区别和用法

人气：407 ℃　时间：2019-08-18 22:34:41

解答

用MUSTN'T的时候,是表示已经肯定了某事,这道题应该要选A的,因为后面那句话已经说了海伦已经去北京.
而如果用CAN'T的话,有带有可能,猜测的意思,带有不确定因素.