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　　June 5 is World Environment Day．This makes us pay more attention to our environment and the need to p　　1　　 it．

　　When Wang Boxuan, a Beijing high Schoolboy, uses up his exercise books, he does not throw them away．Each one is stored at school with hundreds of exercise books given by other students．Then they are sold to a Beijing paper making factory．

　　The paper is r　　2　　 and u　　3　　 again by students and teachers in the school．At the same time, the money made from the sales goes towards schools in Inner Mongolia for p　　4　　trees and grass．This place is one of the sources of the sandstorms that often attack Beijing d　　5　　 spring time．

　　Wang's school is one of the schools in the capital that take part in the “green promise” environmental protection activity．So far, nearly 210, 000 students have taken part in the activity, collecting more than 87 tons of waste paper．

　　With the coming of China's 60th birthday, students are eager to help make the capital a more pleasant place．

　　“There are some environment p　　6　　 in the city, s　　7　　 as sandstorms．” said Wang．“We should do our duty and encourage o　　8　　 to do so as well．”

　　Our Vice-Premier(副总理)has w　　9　　 a letter to the teachers and students to encourage them to go on s　　10　　 environmental protection．