肯定句：主语＋used to＋动词原形… I used to go to the cinema,but I never have time now.
我过去经常去看电影,但现在没有时间了.否定句 A) 主语＋did not use to＋动词原形…… B) 主语＋used not to＋动词原形…… I did not use to go to the cinema.I used not to go to the cinema.一般疑问句 A) Did＋主语＋use to＋动词原形……?B) Used＋主语＋to＋动词原形……? Did you use to go swimming in the river when you were young?
你小时候经常在河里游泳吗? Used he go to school by bike?
他过去骑车上学吗?反意疑问部分用didn't +主语或 usedn't +主语. He used to take pictures there,didn't he?/ usedn't he?