when did it start? 解释

When did it start? when did it start? 解释 是when did it started还是when did it start? When did it start?About ______ ago. When did it start?为什么did用过去式? when did you start doing it?请翻译 When did it start?About ______ago.怎么填? When did you start out? when did you start to______? when did you start to learn english? 怎样回答When did you start school? when did you start （）(hiccup) When did Lu Xun start to write May it be when evening start -When did he start his own business?-_____in 1998______he graduated from his senior high school.答案为什么是 It was when这难道不是强调句吗 when did you start learning English?改为同义句 When did you start learning English怎么回答 when did you start class today是什么时态