I helped him clean the room为什么clean 是原形；那My teacher asked me (clean)the office,clean加ed吗什么情况前后都变,为什么有时后面的一个词就不变过去式

i didn't laugh at him.instead ,i helped him 同义句I helped him ____ ____ ____ at him. 动词过去式后的动词怎么弄?如：I helped him clean the room,为什么clean不用变? ( )what must i i thank him?I don't thing he helped us a lot I helped him clean the room为什么clean 是原形；那My teacher asked me (clean)the office,clean加ed吗什么情况前后都变,为什么有时后面的一个词就不变过去式 We didn't laughing at him but helped him I helped my mum clean the rooms.为什么help用过去式clean却不用呢? I am also be happy that I helped him和I also be happy that I helped him 哪个对? I helped him find his father.为什么find不用过去式? I helped him to find her Father改为同一句 英语关于help的用法I helped him find his father能用 I helped him to find his father I helped my mother clean the room yesterday.还是I helped my mother cleaned the room yesterdayhelped后面的clean应该不用加ed了吧 I don't clean my son’s bedroom．He has to do it______. A. him B. his C. himself if it hadn't been for the fact that he was my brother's friend,i wouldnt have helped him(去if) When I saw the old man __loff his bike,Iran to hin t once and helped him upA.fall B.falling C.to fall D.was falling 这题应该怎么选I ___my grandparents clean their room last Monday.help helped helping But that you helped me,I wouldn’t have succeeded. I didn't have a clean shot. I can;t clean the walls.