close to your vest

You hold your cards close to you so no one can see what you have. In everyday speech, holding your cards close to your vest means not letting other know what you are doing or thinking.

你小心地隐藏着自己的牌，这样，其他人就不能看到你的牌到底是什么。在日常生活中，holding your cards close to your vest意思是不让其他人知道你在做什么或者在想什么。

John, keep this close to your vest but I want to tell you our company is going to merge with a big New York corporation& they'll announce it sometime next week.

约翰，我要告诉你，我们的公司要和纽约的一家大公司合并了，他们下星期内就要宣布。不过你知道就行了，不要往外说。

You can do a better job of bluffing if you hold your cards close to your vest.

如果你hold your cards close to your vest，那么在欺骗（bluffing）时你就会做的更好。