A bag is useful in many ways.

VOA: special.2009.01.25

Of course you guys are savvy enough to know this, but a lot of people get fooled because many people believe that a serving is what's ever in a bag, or a bottle, or a box, and they don't look and see how many servings are actually in it.

大家很聪明,当然看得懂,但还是很多人搞不清它的含义,因为很多人认为所谓一份食物就是指,一包,一瓶或一盒内的食物总量,而没看清整个包装内实际上有几份食物

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

Or, if you are at a party and you're ready to leave but you've left your bag with the host,

又或者，你在一个派对上，你准备要走了，但是你刚才把你的包放在派对主人那里了，

Where 课堂 - SpeakingMax英语口语达人

Software can be added to identify things that are not usually there, like a bag left on a bench.

VOA: standard.2010.04.01

Instead, he paused for a moment and said, "I would marry a donkey " and a big bag of peanuts."

不过出乎意料的是，他想了一会说，“我想娶一只驴子,和一大包花生“

耶鲁公开课 - 心理学导论课程节选

She did for a little while. Then she put her shoes back on and put her old stockings into her bag.

VOA: special.2009.09.05

What is she doing with, you know, a toaster in her bag?

她到底带了什么？包里有个烤面包机吗？

Let me 课堂 - SpeakingMax英语口语达人

The woman asked to see it. When the dishonest tradesman opened the bag, out jumped a cat C not a pig.

VOA: special.2009.01.25

For those of you who are on the run from the FBI, your Visa has run out, or you're sitting next to your ex-girlfriend, now would be a good time to put a paper bag over your head.

被FBI通缉的,签证失效的,还有前女友就坐在旁边的,赶快找个纸袋子把脸给蒙上

耶鲁公开课 - 博弈论课程节选

This expression makes the person left holding the bag responsible for an action, often a crime or misdeed.

VOA: special.2009.01.25

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 crushed seeds are then put into a cloth bag and the bag is hung up.

VOA: special.2009.09.29

A company based in the United States called GrainPro makes another kind of airtight bag.

VOA: special.2011.02.01

Ransie Bilbro took a small bag from a pocket in his pants.

VOA: special.2009.11.14

The astronauts made the connector from a plastic bag, cardboard and tape.

VOA: special.2009.07.22

Then cover the top of the pot with a see-through plastic bag.

VOA: special.2011.04.26

The toilet is a single-use bag made of environmentally friendly plastics.

VOA: special.2010.03.15

Store the unused part in the refrigerator in a plastic bag.

VOA: special.2009.04.28

Hold the bag in place with a rubber band.

VOA: special.2011.04.26

Each 23 kilogram bag of oysters he receives has a tag that marks the area it came from.

VOA: standard.2010.05.08

Mpyisi says the union is a mixed bag of failed states, countries struggling with democracy, and success stories.

VOA: standard.2009.07.02

Passengers are being encouraged to check ahead with their airlines, to arrive an hour earlier than normal and to bring only a single carry-on bag with them.

VOA: standard.2009.12.27