问题描述: jack,with his father is climbing the hill为什么用is不are,climb为什么用ing形式 1个回答 分类:英语 2014-10-05 问题解答: 我来补答 这句话的主语是Jack,不是Jack and his father ,with his father 是附带着的,主语是一个人用单数.进行时用ing,楼主复习一下时态吧 展开全文阅读