我会在下个月把借你的钱还清。

I will ___pay back the money I borrowed from you next month.

他发誓要让那个背叛他的朋友付出代价。

He swore to ___pay back the friend who betrayed him.

我请她吃饭来回报她的好意。

I ___paid back her kindness by treating her to dinner.