My lips are sealed.

我一定会守口如瓶的。

I won't tell a soul.

我不会告诉任何人的。

I'll take it to my grave.

我到死也不会说的。

It won't leave this room.

这话绝对不出这个房间。

Wild horses couldn't drag it out of me.

君子一言驷马难追。

好奇宝宝一定忍不住再补一句“你怎么知道的”？

A. How did you find?

B. How did you find out?

你觉得哪个正确？

答案：How did you find out?

你是怎么知道的？