Bài 3: Complete sentences using given words 
        save         reuse         waste          clean up           reduce 
6. Before the festival , people will..........................all the streets .
7. The scientist will explain some techniques on how to.....................household things .
8. Using these healthcare kits will help .................the environmental risks to your health .
9. The rescue team will take the elephants to another place so that they can ..............................their lives .
10. Please do not ....................electricity because there will not be enough for us to use this winter .