something interesting happening/happen/happened/happens

something interesting happening/happen/happened/happens 用happen,happening,happened造句 something happens和something happen happen,happens与happened三者区别? was happened,was happening,happen,happened,happening的用法及区别 where happens something?Where does something happen?有什么区别 a terrible thing is (happen) A.happen B.happened C.happening 英语翻译A.happened to B.was happened toc.was happening D.happen what happening?如果错了,解释以下what happened?为什么不能改为what did happen what's ____on monday?A.happen B.happened C.happening D.has h happened and happening happened,happening为什么?