题目

一篇英语完形填空答案
In the 13th century,Marco Polo traveled a long way to China.He was a famous Italian traveler.During his stay in China,he saw many wonderful things.One of the things he discovered was that the Chinese used paper money.People in western countries did not use paper money until the 17th century.However,people in China began to use paper money in the 10th century.
Paper was invented by a Chinese about 2,000 years ago.His name was Cai Lun .He then put these pieces of paper together and made them into a book.
Now paper mainly comes from trees.We use it every day.sometimes we waste a lot of it.If we keep on doing so ,people have to cut down many more trees.Then there will not be any trees left.If there are no trees,there will be no paper.
So how can we save paper?When we are making notes,we can use both sides of every piece of paper.We can buy drinks in bottles instead of those in paper packets.We can also use cotton handkerchiefs and not the paper ones.When we go sh

提问时间：2020-10-26

答案

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