So, what's your plan B?
你的下一个计划是什么？ /你的第二套方案是什么？
A: I think that I won't get into Yale University.
我好像考不上耶鲁大学。
B: So what's your plan B for attending a university?
那么，你的第二选择是什么？

That's all I need.

我需要的就是这些。
A: I heard you don't have much money these days.
听说你最近手头不宽裕。
B: Bat I have enough food. That s all I need.
但是我有足够的吃的。这些对我来说就足够了。