脐带的静脉有() A.两根 B.没有 C.四根 D.三根 E.一根 发布时间:2017-09-13 11:46 │ 来源:www.tikuol.com 题型:单项选择题 问题: 脐带的静脉有()A.两根B.没有C.四根D.三根E.一根
题型:单项选择题 The task is so hard that he_______ finish it on time.[ ]A.shouldn't B.needn'tC.can't D.mustn't 查看答案