“我请你吃午饭，怎么样？”用英语怎么说？

Can I treat you a lunch?

I invite you to lunch,OK?

I'll treat you to lunch,ok?

treat you to ...请某人...

How do you like to have a supper with me?

I take you out to lunch,how about that?

在生活中，如果别人开口说 take you to 餐厅酒吧电影院演唱会什么的，就说明这人会为你付钱，请客。

还可以说
I buy you lunch,how about that?
直接表示了我出钱请你了。

外国人都是AA制 你请别人吃 他肯定以为你有事求他