The old man was very strict and he didn't let us ______(come)in.这题为什么填原型?---what should i do?---_____go and say sorry to him.这里为什么要填Why not,而不能填Why not you?

The old man was very strict and he didn't let us ______(come)in.这题为什么填原型?---what should i do?---_____go and say sorry to him.这里为什么要填Why not,而不能填Why not you?
The old man was very strict and he didn't let us ______(come)in.这题为什么填原型?
---what should i do?
---_____go and say sorry to him.这里为什么要填Why not,而不能填Why not you?

The old man was very strict and he didn't let us ______(come)in.这题为什么填原型?---what should i do?---_____go and say sorry to him.这里为什么要填Why not,而不能填Why not you?
您好,很开心为您解答
前一题是因为let sb do sth,即let后接不带to的动词原形
后一题因为why not do sth是固定搭配,why not do sth=why don't sb do sth
希望对您有用
祝您学习进步,天天开心
望采纳谢谢

1. let sb do sth 所以用原形。

2. Why not=Why don't you （Why not后是没有you的。）如果用Why don't you也是可以的。

   
   

let sb. do sth.让某人做某事
why not do sth.为什么不做某事