used to的一般疑问句有两种构成方法:
1)将used提前至句首,结构为:Used + 主语 + to do sth...?
2)将did提前至句首,结构为:Did + 主语 + use to do sth...?
例如:
Used he to get up early?
= Did he use to get up early?
2. used to的反义疑问句有两种构成方法,例如:
1)He used to smoke,didn't he?
2)They usedn't to like opera,did they?