Nature is amazing! Take a close look at the world of insects, and you’ll discover many unbelievable things. Consider butterflies, for example. ___1___ They can show their wonderful flying skills with their wings. On summer days, you always see them flying freely over flower gardens and wild fields. ___2___ 

The process includes four stages (阶段). In the first stage, female (雌的) butterflies lay a small and colorful egg on a leaf or a stem (茎) of a plant.

In the second stage, it becomes a walking insect. This insect is called caterpillar (幼虫). It now has legs, eyes and a large body. ___3___ A new life has begun, but it is still not a butterfly.

The next stage is known as the “pupa (蛹) stage”. After growing big, the caterpillar covers itself in the nice protective blanket (保护层) and goes to sleep.

___4___ It looks quite different. It now has six legs, a mouth, eyes and wings.

After a few weeks, this adult butterfly lays her eggs, and the cycle (循环) begins all over again. ___5___ Look around the natural world, and you will learn many truly amazing things.

A. The caterpillar can eat, walk and see.

B. Butterflies have a good sense of smell.

C. This is just one example of the wonders of nature.

D. Butterflies are colorful and they have strong wings.

E. But do you know how butterflies become the flying insects?

F. In the last stage, the blanket breaks and a wet, weak butterfly appears.