Most of us have three meals a day .We take food for granted(想当然)。And we don't think about it. 1 experts argue a food crisis(危机)is coming.This crisis is going to make us 2 the way we think about food.

 Food is in great need 3a growing of world population.By 1960,the population was three billion.It doubled to six billion by 1999.By 2050,this planet will need to  4 at least nine billion people.As a result,the food prices get higher and higher.

 So,what can a   5 ,crowed world do?One suggestion is to eat less meat.Meat uses more natural resources(资源)than grains(谷物) .It requires more  6  to produce one pound of meat than to produce one pound of grain. It also requires between 5 and 10 times more water than vegetables. So ,eating less meat will  7  more land for farming,and it will save water.

 To eat less meat,people will need to change their eating habits. That will not be easy. Americans, for example,have 8 loved meat.  In general, They eat twice as much meat as people in other countries.At the same time,in developing countries like China and Brazil,sales of meat have doubled in the last 20 years.   9  will double again by 2050.Growing need of meat wil continue to put pressure on natural resources.

 World  population is increasing,resources are becoming fewer,and food prices are rising.Therefore, we need to rethink what  we eat every day. For meat lovers, we don't  need to give up meat  10 .But we need to eat more grains and less meat.

Empathy(同情心) lets us feel another person's pain and drives us to help. Do any other animals feel empathy? Scientists recently found that rats(老鼠) do, too.

    Most people don't like rats. In many people's eyes, rats are only bad. But Jean Decety and his partners at the University of Chicago did an experiment. It showed that rats are kind, warm-hearted animals. They can feel each other's pain.

Scientists placed pairs of rats in plastic cages(笼子) for two weeks. During this time they got to know each other. Then they put one of the rats from each pair into a small container(容器) in the cages. The small container had a door. It was so designed as to fall to the side when the free rat touched it. Many of the trapped(困住的) rats squeaked(吱吱叫) to show their discomfort. The other rats of the pairs could see their suffering friends clearly.

In most pairs, the free rats would become very worried about their friends. They kept trying to save their friends again and again throughout the month. Scientists put the rats' favorite chocolate in the cages, but the rats didn't eat it until they had saved their friends successfully. Scientists also found that female rats seemed to act more empathetic than male rats.

    “The results are the first to show that rats take action in response to another's trouble,” Decety said. “Monkeys and chimpanzees have similar behavior. But unlike those animals, rats can be ready used in laboratory studies. They will help us to learn which parts of the brain lead to empathy and helping behavior and whether empathy is natural.”

    People like dolphins because they are both lovely and clever. They have an 1 IQ (智商).

Dolphins can 'talk'. Scientists try to ‘talk' with dolphins, and the results make them 2. They find that dolphins 3 understand them so well.

4 animals enjoy playing, but dolphins like to make their games different. On a beautiful day in 1997, scientists on a beach 5 a little dog going into the sea. They were surprised to see the dolphins come up to the dog and then start throwing(扔) it into the air. The dog 6 the 'game' and kept playing with the dolphins for over an hour.

    Dolphins live in a very different world from 7, but they are very good at our 'IQ tests(测试)'. For example, in the picture above, a dolphin jumps 8 the water when he hears a whistle noise(哨声). He does this because he will get a fish 9 an award.

    There is 10 much to learn about these lovely friends.

Are Sports Important?

    Sports are all around us. We watch and read sports news. There are also sports clubs, and even sports-only channels(频道) on TV. In many countries, players make millions of dollars every year. But why are sports so important? They're only games, right?

    Our readers answer:

    Vlad (Ukraine乌克兰)

    Sports bring people together. In 2006, our team was able to play in the 2006 World Cup for the first time. Everyone was happy. Rich and poor, old and young, men and women—everyone was in the streets together!

Mike (U.S.A.)

    Sports bring people together, but they divide them too. Fans of different teams fight all the Time-they shout and hit each other. And here's another example: My brother plays high school baseball. Last week, his team played an important game. At the game, two parents fought about a call .

    Come on … baseball is only a game! Sports are so competitive (有竞争力的) these days. It's all about winning. Then the game isn't fun.

    Oba (South Africa)

    Right now, some of the world's best soccer players are from African countries, and the 2010

    World Cup games will be held in South Africa. Yes, some players make a lot of money—maybe too much, but sporting events (like the World Cup) bring tourists and money to countries and people. And that is good for Africa.

    The world of the out-of-doors is full of secrets (秘密). And they are    1interesting that quite a lot of people are busy 2them.

    All around us are birds, animals, trees and flowers. The facts about how they3 and grow are as interesting as anything could be.

    Do you know that one of the great presidents of the USA 4 hours and hours5birds? A businessman who lived near New York became so 6in insects(昆虫) that he began to get 7 together. He now has more than one thousand different kinds of insects carefully 8in glass boxes.

    Come up with me, and I will help you find some nature's secrets. Let us go9 through the woods and fields. Here we shall find how a rabbit tells the others there is danger. We shall 10 a mother bear and her young ones as they look for11and get ready for winter sleep. We shall watch bees(蜜蜂)dancing in the air to let other bees know 12 they can find food.

    I will 13 you many other interesting things, but the best thing that I can14 you is to keep eyes and ears15 when you go out of doors. Nature tells her secrets only to people who look and listen carefully.