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How to protect the environment becomes one of the big problems in the world.
     1.________
We can find the rubbish not only pollutes our environment but also harm people's health.
     2.________
So we should throw rubbish onto the ground.
     3.________
Some factory are pouring waste water into rivers,lakes and fields.
     4.________
It can pollute plants;sometimes it can kills lots of fish.
     5.________
We must keep our environment clean and untidy.We have only one earth.
     6.________
We must try our best protect her,and make our home more beautiful.
     7.________