I'll tell you what.
我告诉你吧。
A: Are you sure you can't lend me five thousand dollars?
B: Hmm...I'll tell you what. I'll lend you four thousand dollars, but you have to pay me back next week.
A: It's a deal.
甲：你确定无法借我五千元吗？
乙：嗯……我告诉你吧。我将借你四千元，但你必须下周还我。
甲：一言为定。
