In the 13
th century, the famous Indian traveller, Marco Polo, travelled a long way to China. He saw many wonderful things. One of the things he discovered was that Chinese used paper money. In western countries, people did not use paper money until the 15
th century. However, people in China began to use paper money in the 7
th century.
A Chinese man called Cai Lun invented paper almost 2,000 years ago. He made it from wood. He took the wood from trees and made it into paper. He then put these pieces of paper together and made them into a book.
Now paper still comes from trees. We use a lot of paper every day. If we keep on wasting so much paper, there will not be any trees left on the earth. If there are no trees, there will be no paper. Every day, people throw away about 2,800 tons of paper in our city. It takes 17 trees to make one ton of paper. This means that we are cutting nearly 48,000 trees every day. Since it takes more than 10 years for a tree to grow, we must start using less paper now. If we don’t, we will not have enough time to grow more trees to take the place of those we use for paper.
So how can we save paper? We can use both sides of every piece of paper, especially when we are making notes. We can also use cotton handkerchiefs（手帕） and paper ones. When we go shopping, we can use fewer paper bags. If the shop assistant does give us a paper bag, we can save it and refuse (拒绝) it later.
Everyone can help to save paper. If we all think carefully, we can help protect trees. But we should do it now, before it is too late.
小题1:When he was in China, Marco Polo __________ .
| A．discovered Cai Lun invented paper | B．learned to make paper |
| C．saw many wonderful things | D．read a lot of books |
小题2: People in western countries first used paper money in the _________ century.
小题3: About ________ tons of paper are thrown away every day in our city.
| A．1,700 | B．2,000 | C．2,800 | D．48,000 |
小题4: Which of the following is the way of saving paper?
| A．To use both sides of every piece of paper. |
| B．To use the paper bags from shops more than once. |
| C．To use cotton handkerchiefs and paper ones. |
| D．All of the above. |
小题5:Which is the best title（题目） of the passage?
| A．Saving paper. | B．The history of paper. |
| C．Cotton handkerchiefs back again. | D．Cai Lun, the great inventor. |
t we eat every day.
r(粉末). Because of melamine, it’s reported that 4 babies died and more than 50 thousand babies are affected since 2008. Sanlu, a famous milk powder factory was closed. What’s worse, milk powder with melamine appeared in 2011 again. Problems of food safety, for example, poisonous rice, lean meat powder(瘦肉精) and plasticizers(塑化剂) are becoming more and more serious.
If you happen to work in front of the computer, it is best to take a break every once in a while. Something dirty can cause redness and they will make you feel uncomfortable. It is bad for your eyes, too. If this happens, the best way is to clean your eyes by using cold water. You must also try your best to protect your eyes from harmful things. For example, sunglasses are not just for fashion but they can also serve as a great way to protect your eyesight form UV rays. 
the right kind of food, his eyes will stay in good condition for a long time.
