英语：what did you do 为啥后面的就不用变过去式了呢?

英语：what did you do 为啥后面的就不用变过去式了呢? 请问一下什么情况下在过去式的句子里,前面用了did,后面就不用过去式了? What do they do last night为啥do不用过去式 What did you do on National Day?的过去式答语 did it 或者是 did you 后面的动词变过去式还是原型? 如果是did you have your supper and do your homework呢?do要变过去式吗 这句话对么 缺什么么what do you want from me为啥就对了呢 what did you do during the holiday英语作文 80字 国庆节 用过去式 过去式的问句中前面的do变成过去式了后面的动词还要变过去式吗 为什么过去式后面加不了过去式.比如what did he do last week.为什 do的过去式“did”后面的动词恢复原形吗 What did you mean by saying that?中为什么不用did要用do拜托各位了 3Q