Just be careful not to let the cat out of the bag, or someone may leave you holding the bag.

VOA: special.2009.01.25

And she looks like she's about to pass out because her bag is so filled with so many objects. I mean,

她看起来就快晕过去了，因为她提的袋子实在是装了太多东西了。我是说，

Let me 课堂 - SpeakingMax英语口语达人

the stuff that's falling out of the bag is just ridiculous.

从包的边缘掉出来的东西都是让人匪夷所思的玩意。

Let me 课堂 - SpeakingMax英语口语达人

If you tell about something that was supposed to be a secret, we say you let the cat out of the bag.

VOA: special.2009.09.27

The phrase to be left holding the bag is as widely used as the expression to let the cat out of the bag.

VOA: special.2009.01.25

Some of the oil will flow out of the bag and can be collected.

VOA: special.2009.09.29

Another widely-used expression is to let the cat out of the bag.

VOA: special.2011.05.22