How many backpacks have you owned since you went to school?Backpacks（1）______（become） common and popular among students in the past 30 years.If your backpacks become old,will you just treat them as rubbish and throw them away?Five years ago,a research（2）______（show） that 85% of the old backpacks ended up in rubbish.But as we know,most backpacks are produced from different（3）______（material）.If we throw them away,they will be bad（4）______our environment.
Although some of the old backpacks are no longer of their right color or size,there are still many things you can do with them.Here are some（5）______ （use） ways for you.For example,do you feel it difficult to find（6）______（you） tools in the house?You can solve this problem by（7）______ （make） use of your old backpacks to store all kinds of tools.Also,it is（8）______wonderful idea that you can put your old backpacks online for sale.Besides,offering your backpacks to other poor kids is another good choice,as those old backpacks may make their life（9）______ （convenient） than before.
All in all,old backpacks are still of great value as long as we put them into use(10)______ （wise）.Remember:rubbish can be turned into treasures!