With the development (发展) of society (社会), life becomes more and more important. Some people think it is very  to do. In fact (实际上), we can do a lot of things .

    First, as a , some of us can ride a  to school, or walk to school every day. It can  energy and it is good  our healthy (健康). Second, when we leave the classroom, remember to  the lights to save electricity. And third, we should  our homework on both sides of the paper. It's a good  to save paper, and to save trees.

    If everyone can  a low-carbon life, the world will become a better place.