Sometimes people calloursa "throw-away society". That means that we're always throwing away old things and buying new ones. Many times, you no longer need something, but someone else may just need to buy one. For example, if your baby doesn't like his toy car any longer, why not give it to a family who has a little kid?
Here are some other ways to help the society save resources(资源):
Use the other side of the paper so that fewer trees will be cut down.
Use rechargeable (可再充电的) batteries for your electric toys, MP4 players, cell phones and cameras.
Choose reusable travel cups instead of disposable (一次性的) paper or plastic cups.
Take your own cloth shopping bags instead of using the plastic bags that are offered when you go shopping.
Drink tap water instead of buying bottled water.
And there are some things you can exchange with your friends, for example, books, toys, even clothes. It's a way for everyone to get something new without spending any money and without throwing many things away.
