Is the girl (having) dinner with her father and mother at home?为什么要用having.

题目

Is the girl (having) dinner with her father and mother at home?为什么要用having.
不是第三人称用has吗?这里为什么要用having,

答案

be doing sth 正在干什么...现在进行时.
那个女孩正在跟父母在家吃饭吗?
谁说单三了?单三用在普通的现在时...
Does the girl have dinner with her father and mother at home everyday?
那个女孩每天跟父母在家吃饭吗?
The girl has dinner with her father and mother at home everyday．
那个女孩每天跟父母在家吃饭