Caterpillars（毛毛虫）are cute. They star in children's books. They turn into pretty butterflies. And now it turns out they may hold the key to solving plastic pollution.

Like many great findings and inventions, the discovery of a caterpillar that eats plastic was made accidentally. Bertocchini, a biologist in Madrid, was cleaning her hobby beehives(蜂箱）and used a plastic shopping bag to collect the caterpillars which eat wax(蜂蜡）. When she looked at the bag later, she was surprised to see it was full of holes. She decided to look into this plastic-eating wonders of caterpillars with her team.

They offered a plastic bag from a UK supermarket to a group of 100 wax-eating caterpillars. They began creating holes after 40 minutes; 12 hours later, they had reduced the mass of the bag by 92mg. While there have been other creatures that eat plastics, none of them have been able to do so better than these caterpillars.

"This discovery could be an important tool for helping to cut down the problem of plastic waste and save our oceans and rivers," Bertocchini said. "The caterpillar will be the starting point. Before using this finding in a practical way to solve plastic problems, we need to understand the chemical secrets behind the natural degradation(降解）of plastic. Something in the caterpillar一as well as the caterpillar itself—might play a role".

Most friendships die a nature death: people move, change jobs, or start different stages of life. Other friendships, however, end unexpectedly. When a friendship is over and you don't understand why, it can be especially painful. Sometimes a friend ends your relationship without telling you why.

The loss of friendship might be worth reflecting on. Knowing when a friendship is over and why it ends may help you build stronger friendships in the future.

●See if you can find a problem.

When a friendship is over, examine your relationship. Perhaps you remember your friend complaining that you're always late. Maybe you seldom return your friend's phone calls. When a friend ends your relationship, try to find out the reasons why the friendship is over.

●Write a letter to your friend.

Express your feelings about the friendship. Do you miss seeing them? Do you have any regrets? Would you act differently if you were still friends? Make it an honest communication.

●Express your feeling of being hurt or anger.

Write or talk about how you feel in a letter. When a friendship is over, it's important to communicate exactly how hurt you feel and why. Write until you have nothing left to say. When a friend ends your relationship, you do have the right to express yourself.

●Communicate that you are open to pick up the friendship.

When a friendship is over and you want to reconnect some day, send Christmas, or birthday cards. Say hi and send greetings through mutual(共有的)friends. When a friendship is over, don't give up until you're ready.

●Decide to make your present friendships better.

An adviser once told me that simply talking about your relationship strengthens your relationship. Talk to your present friends. Are they happy with your friendship? If a friend ends your relationship, learn something from it.

Do you often have bad moods (心情) because of some trouble? Different people have different ways to improve mood. The following advice can help you find your best way.

★Do something you enjoy, it will keep you away from the bad mood. 【小题1】 What makes you happy? Let yourself do that thing.

★【小题2】 You can have lunch, coffee, or watch a movie with your friend. It’s OK if you don’t like these, you can visit a park with your friend. You can just sit and talk. 【小题3】 You can use the phone to talk with them. They may make you happy.

★Change your environment. You can go for a walk to improve your mood. 【小题4】 You can listen to music or read an interesting book. These activities will help so much.

★Think about your problem by yourself. It helps you find the answers. 【小题5】 You don’t have to be unhappy. Sometimes it is bigger. You just need to spend more time on it.