短文改错

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.________