A（:,2) gets the second columns from A.

But beyond just looking dirty, a filthy (肮脏) keyboard might actually make you sick.

A 2008 study showed that keyboards can be up to five times dirtier than the average toilet seat. How come？

Too often, people don't 2_____ to wash their hands after using the restroom or eating at their desks. In the

latter case, sticky fingers transfer sauces and crumbs (食物碎屑)onto and between the keys. Also, our fingers

rub skin oils onto the keys. Thus, a keyboard can become a 3_____ place for germs to grow.

One common bug that researchers have found is staphylococcus aureus (金黄色葡萄球菌). It is a classic

cause of food 4_____, signs of which include nausea (恶心) and diarrhea (腹泻). Stomach sicknesses caused

by typing on a dirty keyboard have been dubbed "qwerty tummy" after the "Q-W-E-R-T-Y" keys on a

keyboard.

The threat posed by a dirty keyboard is quite real, but it can be 5_____. The easiest way is to clean your

keyboard regularly. Office cleaning 6_____ say that keyboards should be unplugged, turned upside down and

shaken 7_____. By doing so, you can get rid of most of the crumbs. After that, wipe across the keys using a

soft cloth with a cleaning solution (清洁剂). Another way to solve the problem is using a silicon (硅胶)

keyboard cover. These thin covers are made to 8_____ over the keys. They prevent food from falling through

the cracks and dust from 9_____.