为什么不的英文：
why not?

参考例句：

Why do not they quit smoking?
他们为什么不戒烟呢?

Why don't you have another try?
你为什么不再试一次呢?

Why wasn't she sweating too?
她为什么不出汗呢?

Why not take a chance on it?
为什么不冒险一试呢？

Why not try your hand at merchandising?
为什么不试试推销呢？

Why didn't you cancel it?
你为什么不取消呢?

Why don't you join in the games?
你为什么不参加运动会?

Why didn't you come home?
你为什么不回家呢?

Why can't I sleep in pajamas?
为什么不能让我穿宽长裤？

Why didn't you select a better subject for your composition?
你为什么不选一个更好的作文题?

why是什么意思：
adv. （用作疑问副词）为什么，（用做关系副词）为什么
n. 原因，理由
int. 咦，哎呀，哦，当然，唔

Why are you in such a hurry?
你为什么这样急呢?

Is this why the Yen is so strong?
这是日元如此强劲的原因吗？

Why, I was fast asleep.
怎么，我睡得很熟的呀。

Why is Leo behind time?
利奥为什么迟到了？

Why not fire away at the engineer?
为什么不向工程师提出问题?