jack,with his father is climbing the hill为什么用is不
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
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