A: That was Sherry. She wants me to go to Hong Kong next month.
B: Why don't you?
A: I don't know whether I should go or not.
B: I think you should, but, it's up to you, of course. Do whatever you want.

A: 是雪莉打来的电话。她要我下个月去香港。
B: 你何不去呢？
A: 我不知道该不该去。
B: 我想你该去，不过，当然要由你自己决定。想做什么就去做。

重点解说：

★ Why don't you?的原形是Why don't you go?也就是省略了go一词。Why don't you ~?「你何不~？」是提供意见或劝说时的实用句型。

★ Do whatever you want.「你想做什么就去做。」