阅读理解
Nature is amazing! Take a close look at the world of insects (昆虫), you'll discover many unbelievable things. Consider butterflies, for example. They have beautiful, colorful wings, and strong, fantastic flying skills. On summer days, you always see them flying freely over flower gardens and wild fields.
But
did you know how butterflies become the flying insects? It's one of the amazing wonders of nature. In the beginning, female butterflies lay a small and colorful egg on a leaf or stem (茎) of a plant.
It's hard to believe that the egg will become something completely different in a few days. It becomes a walking insect. This insect is called caterpillar. It now has legs, eyes and a large body. A new life has begun. The caterpillar can eat, walk and see. But it is still not a butterfly.
Soon, after growing big, the caterpillar makes a cover for itself. It covers itself in the nice protective blanket (保护层) and goes to sleep. This stage is known as the "pupa (蛹)" stage.
After a period of time, the blanket breaks and a wet, weak butterfly appears. It now has six legs, a mouth, eyes and wings. Shortly, the wings fill with blood, and the beautiful, colorful butterfly spreads its wings and flies away.
After a few weeks, this adult butterfly lays her eggs, and the cycle begins all over again.
This is just one example of the wonders of nature. Look around the natural world, and you will learn many truly amazing things.