高中情态动词题1,your sister must be at home,_______she?A,isn't Bdoesn't _英语解答

高中情态动词题
1,your sister must be at home,_______she?
A,isn't Bdoesn't Cmustn't can't
2,they had to catch the early bus,________they?
Ahadn't Bdidn't Cmustn't Dcan't
3,He must have been abroad,_______he?
Ahaven't Bhasn't Cisn't Ddidn't
请问关于情态动词的反义疑问句怎么判断,

人气：360 ℃　时间：2020-06-12 19:52:41

解答

1. A your sister must be at home. 这里MUST表推测,相当于your sister is at home. 反义疑问句,前肯后否,所以用isn't
2. B. they had to catch the early bus 这里had to 是必须的意思,过去时态,用do的过去时态,前肯后否,所以用didn't
3. B He must have been abroad,这里MUST表推测,相当于He has been abroad.反义疑问句,前肯后否,所以用hasn't