阅读理解。
In the 13th 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 moneyuntil the15thcentury. However, people in China began to
use paper money in the 7th century.
A Chinese man called Cai Lun inventedpaper 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, therewill beno paper. Every
day, people throw away about 2,800 tons of paper inour city. It takes 17trees 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 papernow.If wedon'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? Wecan use both sides of every piece of paper, especially when we
are 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 apaper 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.
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
2. People in western countries first used paper money in the _________ century.
A. 17th
B. 15th
C. 13th
D. 7th
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
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.
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.