题目

A zebra (斑马) and a horse are friends. One day ,they talk about their clothes. The zebra says to the horse, Your white clothes are beautiful. I want them, too. So the horse lends (借给) his white clothes to the zebra. The next day ,the zebra meets a tiger. The zebra is afraid of the tiger and runs away, but the tiger runs after him. He can see the zebra's white clothes clearly.The zebra takes off the white clothes. Then the tiger can't see him among the trees. At last the zebra returns (归还) the white clothes to the horse.Don't admire others. Your things are the best for you.【1】Th地衣等能在岩石表面生长，它们的生长又腐蚀了岩石，这说明生物体既能________，又能________。