People cut down trees for farms, houses, to make bread, to cook, to keep their houses warm and to make paper. When people cut down trees they destroy forests. Over the past 50 years people cut down almost 50% of the rain forests. Paper comes from trees. When we use a lot of paper we must cut down a lot of trees. Trees give us clean air and oxygen. Trees are homes for many animals and birds. So trees are very important for us. We must take care of them.