al. we can't imagine what the life will be like without it.everyone should do his best to save electricity. don't forget to turn off lights or other electric machines when we finish working.

　　save forests. they are useful .please stop cutting them down and use recycled paper instead. make our world a green one to live in.

　　recycle useful rubbish. plenty of rubbish can be recycled like cans,paper, bottles, and so on. we can save resources in this way.

　　3、控制人口

　　the problems of large population

　　    it is reported that the world's population was 6 billion in the year 2,000, and it is growing faster and faster. the world's population problem is the greatest one because it brings lots of problems, such as water resources problem, more and more people losing their jobs and so on. these problems are mainly in the developing countries because the population of the developing countries is over 4/ 5 of the world's popuation. so china, t

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