题目内容：

There’s nothing worse than sitting next to someone whose breath smells bad. In ancient China, people used to eat a special plant to make their breath smell better. 1.

How your breath smells says a lot about your health. Scientists can now tell whether or not somebody has a disease just from a simple breath test.

2.Breath is made up of waste chemicals（化学物质） that the body makes, Scientists from the Swiss Federal Institute of Technology found that these chemicals are different for each person. In fact, they’re just like fingerprints (指纹)-that's why scientists sometimes call them "breathprints”.

Compared to other kinds of tests, a breath test is much quicker. 3.

Breath tests are also a lot easier to do than regular tests, as people only need to blow into a special machine. 4. It has been useful in finding early signs of problems such as stomach cancer.

5.And hopefully some day, visits to the hospital will be a quicker and easier for everyone.

A. How does it work?

B. Now we use gum instead

C. This machine will help to test their breath

D Instead of taking hours, it only takes a few minutes

E It's much cheaper to do a breath test than other tests

F. There are many ways to make your breath smell better

G. Now, scientists are trying to use breath tests as much as they can