阅读下面材料，用不多于1个单词的正确形式填空
It’s very important 61 we all recycle. In nature, everything is 62 (use) again. 63 example, when 64 (a) animal dies, it becomes another animal’s food. Nothing is wasted. But humans have created things like plastic bags 65 can’t be broken down(分解) by nature. Our rubbish kills animals and pollutes water and soil. If we continue making too much rubbish, the problem will only get worse. If nature can’t reuse the rubbish, we must recycle it. We should clean up the rubbish we’ve 66 (make) because nature can’t.
Recycling is also the 67 (rightly) thing to do for another reason. The earth is rich in natural materials like water and 68 (tree), but these materials are not endless. We use up our natural materials much 69 (fast) than the earth is able to reproduce(再生）them.
Recycling can help us save the earth, 70 let’s take action（采取行动） right now.