问题描述: I helped him _____ his homework.A.doing B.do C.did D.does 1个回答 分类:英语 2014-11-11 问题解答: 我来补答 选Bhelp sb do表示帮助某人做某事(的全过程)help sb doing(是一种瞬间动作) 展开全文阅读