The factory used coal last year.

    This is our small world. It is the only one. It is our duty  (protect) it for ourselves and for our children. If each of us  (do) something to help our earth, we will all have a better life. Our air and water  (be) cleaner. It's not too hard to help our earth. We really only need  (try).

    In fact, all of us can  (make) a small change in the way we live. It will make a big difference to our environment. Here are a few tips  (help) save our world.  (not throw) away so much. Pick up litter in the streets. Turn off lights when leaving a room. Turn off televisions and shut down computers when they are not in use.  (bring) your own shopping bag when you go  (shop) . Save water! Take a shower rather than a bath. Turn off the tap while  (clean) your teeth.

Old books shouldn't be . Maybe they are useful in your later life.

Drinking cola too much our health.

We must to keep the soil in place.