用DID提问的疑问式 提问的动词应接原形吗

是的。
Did you finish your work?
Did he come here before?

没错，一定要原形

yes它是由陈述句改过来的.eg: You went home by bus yesterday. 提问时需加入助动词，并且助动词提前， went 是go的过去式，did 是过去式的助动词。 所以，这句话的疑问句为 Did you go home by bus yeaterday? 而回答则为 Yes, I did. or No, I didn't

是的，一定要这样