'USA? Britain? Which country is better to study in?' We often hear such discussions. As China opens its door, it is a dream for many Chinese students to study abroad. They want to learn about the outside world.
     It's true that studying abroad can help students develop themselves. Their foreign language skills will be improved and it may be easier to find jobs.
     But there are problems that should be considered. Language is the first. Students must spend a lot of time learning another language.     
     Students must also learn to live without parents' care and deal with all kinds of things they haven't had to do before, like looking after themselves. There are reports about Chinese students abroad running into an ocean of difficulties and giving up finally. When they have to take care of themselves, it is hard for students to study well. 
     Finally, studying abroad brings a heavy burden (负担) to the family. For most Chinese parents, the cost of studying abroad is very high. But is it worth it?
     We know that there are many famous people who have achieved success through their hard work in China. Liu Xiang is a good example. Once an American teacher invited him there, but he refused. He kept training hard with his Chinese teacher. He surprised the world when he won a gold medal at the Athens Olympic Games. So when you wonder which country is better to study in, think again.

    Maybe you pride yourselves on only sleeping a few hours a night. However, are you feeling tired and sleepy throughout the day? Do you have a hard time keeping your eyes open as you study? Have you nodded off while driving? If you can answer “Yes” to any of these, it shows you could not have enough sleep.

    It is suggested that most adults need seven to nine hours' sleep. As for teens, they need even more. If you aren't getting enough sleep, you should：

    Avoid caffeine(避免咖啡因)

    You should avoid drinking caffeinated drinks such as coffee, tea and soda for at least 10 hours before you go to bed.

    Avoid eating big meals before sleeping

    Eating a big meal can make you feel sleepy, and it can make you feel uncomfortable and prevent you from sleeping well.

    Build a healthy sleep environment

    With the light on, can you have a good sleep? Of course not, and you'd better keep your bedroom dark and cool.

    Avoid using electronics before sleeping

    The light from electronics can keep you from falling asleep. Try reading or listening to quiet music instead.

    Please get enough sleep from now on.

{#blank#}1{#/blank#}⑴The most unusual museum in London is the Science Museum. In most museums, there's no shouting and no running, and people aren't allowed to touch the exhibits (陈设品). But the Science Museum is different. It's noisy! People can talk about what they will see and do there, and some of the machines are noisy as well.

{#blank#}2{#/blank#}⑵When I visit the Science Museum, I go to the Launchpad (发射台). This is the most popular room because there are lots of physics tests. We can also learn how astronauts travel into space and back again here. I'm really interested in those kinds of things, so it is my favorite room.

{#blank#}3{#/blank#}⑶On the second floor there is Human and Nature room. We can compare our speed with animals there. If we aren't quick enough, the lion will catch us! There are also rooms on transport, the environment and space technology, as well as math, physics and chemistry.

{#blank#}4{#/blank#}⑷We can do a lot of things in this museum, but we have to obey some rules as well. For example, we mustn't take photos of the exhibits in the museum. But we can buy postcards of them in the museum shops.

{#blank#}5{#/blank#}⑸Most important of all, the Science Museum is free. That means we can drop by for a few minutes or we can stay as long as we like—it's open from 10: 00 a. m. to 6: 00 p. m.every day except Monday. So if you go to London, make sure you visit the Science Museum. It's my favorite museum in the whole world.

    A ratio compares two numbers. For example, if you have 3 pens and 4 pencils, the ratio of pens to pencils is 3 to 4. {#blank#}1{#/blank#} 3 to 4, 3:4 and 3/4. One type of ratio is expressing (表示) numbers as a percent. A percent is the ratio of a number to 100. In other words, a percent compares one number to 100. The percent means "per hundred". {#blank#}2{#/blank#} You can use "%" to express percent. So 35% means 35 out of 100, and 15% means 15 out of 100. {#blank#}3{#/blank#} Probability means the chance (可能) of some things happening in the future. For example, if there is a 90% chance of rain, 90 times out of 100, it will rain. That is a very high probability. However, if the weatherman says that there is only a 10% chance of rain, then 10 times out of 100, it will rain. {#blank#}4{#/blank#}

    You can also express probability by using ratios. {#blank#}5{#/blank#} 5 of them are black while only 1 of them is red. If you choose a pen at random (随机地) from the pencil box, then the probability of choosing a black Den are 5 to 6, or 5/6. On the other hand, the probability of choosing a red pen is only 1 to 6, or 1/6.