sentences: if something is required to create something else then that something is needed to wreck that something else & creating pencil requires equipment down reaching ->  cut trees are needed to make paper  cut trees are needed to make paper & decreases are a mean of artificial curing ->  cut trees are a kind of resource that is needed to make paper  cut trees are a kind of resource that is needed to make paper & waste reduces the jump needed to wreck something -> recycling paper reduces the cutting of trees