Will you go to the dinner party?I won't go until Tom is invited.这里为什么要用is invited?

Will you go to the dinner party?I won't go until Tom is invited.这里为什么要用is invited?
Will you go to the dinner party?
I won't go until Tom is invited.这里为什么要用is invited?

Will you go to the dinner party?I won't go until Tom is invited.这里为什么要用is invited?
在英文里面,有一种语法叫做被动语态.
这里的until引导的是时间状语从句,主句用将来时,从句用现在时
所以,结合两点,用is invited