为什么不加入我们练习英语呢?用英语怎么说

why not join us to practise English?

Why not join us and practising English?
不好意思，搞错了，后面practise应该用原形。
所以是：
Why not join us and practise English?
当然也可以用：
Why don't you join us and practising English?

Why not join us and practise English?
也可以 Why don't you join us and practise English?

Why do not you join us to practice English do

Why not join us to practice English?