Many young people use computers, but few of them know to look after them. Remember the following when you use your computer.

　　Keep your computer in a cool room. Too much or too little heat is bad for computers. Most computers work best at temperature of 5℃-30℃

　　Don’t let people smoke cigarette (香烟) near your computer. Smoke of all kinds is very bad for many parts of a computer and can cause many problems

　　Don’t eat or drink when you are near your computer. Pieces of food and a little water in the keyboard can also cause many problems

　　Make sue the screen is the correct distance from your eyes. If you wear glasses, make sure these glasses are correct for using with the computer. Some people use a different pair of glasses when they use computers

　　Keep your screen clean and don’t have it too bright. A dirty screen can hurt your eyes. A very bright screen can also be bad for your eyes.

　　1. according to the passage you should use your computer___

　　A. in a small room B. in a big room

　　C. in a cool room D. below 5℃

　　2. when you work on the computer, you can ____

　　A. wear glasses B. smoke cigarette

　　C. eat some hamburgers D. clean the keyboard with water

　　3. if you want to look after your eyes, you should ____ when you use computers

　　A. buy a pair of sunglasses B. keep your screen clean

　　C. have your screen very bright D. keep your screen near your eyes.

　　March 21 is World Sleep Day. How’s your sleep recently?

　　The Chinese Medical Doctor Association asked 8,200 people in China about their sleep. More than 36.3 percent of them said they often sleep badly. The study also finds that many students have only 5 hours of sleep a day. According to the US National Sleep Foundation, teenagers need 8.5 to 9 hours of sleep every night

　　What cuts into their sleeping time? Homework. Also , school starts early in the morning. But bad sleeping habits also play a role.

　　Do you like to have a look at your mobile phone before going to bed? The survey finds that 60 percent of people check their phones before they sleep. They read news, check their WeChat (微信)and micro blog (博客) messages, or chat with QQ friends.

　　It’s important for us to get enough sleep. If we can’t get enough sleep, we’ll feel sleepy and think slowly. And sleepy kids are often unhappy, says a study by the US National Foundation.

　　103 Dates 枣

　　70 Mashed potatoes

　　56 Boiled potatoes

　　52 Orange juice

　　49 Chocolate bar

　　30 Whole milk

　　We can’t change our school time. But there are still ways to get better sleep. Stay away from soda, coffee and tea at night. They make it hard to sleep well. Leave your mobile phone and computer on your desk. Watch less TV.

　　Look at these numbers in the box. They are glycemic indexes (血糖生成指数). The bigger the number is, the better that food can help you to get better sleep.

　　4. how many hours of sleep do teenagers need every night according to the passage?

　　A. about 12 hours B. about 9 hours

　　C. about 4 hours D. about 5 hours

　　5. many students can’t get enough sleep because ___

　　A. they play sports too much and feel excited

　　B. they use mobile phones during the day time

　　C. they drink too much soda, coffee and tea at night

　　D. they have too much homework and bad sleeping habits

　　6. when people can’t sleep well, they may____

　　A. feel sleepy and unhappy B. go to bed earlier next day

　　C. change their school time D. go to work late next day

　　7. in the passage if you want to get better sleep, you should___

　　A. chat with your friends B. eat the right food

　　C. put your phone beside you D. be away from food like dates