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.

    The computer is fast, and never makes a mistake, while people are too 1 and full of mistakes sometimes. That's what people often say when they talk about computers. For over a quarter of a century, scientists have been 2 better and better computers. Now a computer can do a lot of everyday 3 wonderfully. It is 4 used in factories, hospitals, post offices and airports. A computer can report, decide and control in almost every field. Many computer scientists are thinking of making the computer “think” like a man. With the 5 of a person, a computer can draw pictures, write music, talk with people, 6 chess, recognize voices, translate languages and so on. Perhaps computers will one day really think and feel. Do you think the people will be 7 when they find that the computer is too clever to listen to and serve the people? No, people will make 8 use of the computers in the future. Man is always the master of the computer. The computer 9 only with the help of man. It cannot take the 10 of man.

    You're thirsty and you get yourself a glass of water. Do you ever1how old that water really is? The glass of water that you're2may have fallen from the sky as rain only last week. However, water itself has been around pretty much as3as the earth has! In fact, 4oceans, seas and rivers cover 70％of the earth, there is a 5 supply(供给)of water, which keeps on moving round the earth. This is6of what's known as the water cycle. The sun heats up water and it turns into clouds, which are7from water vapor(水蒸气).When the clouds become8, the water falls back onto the earth as rain. Of course, clean water is absolutely essential for good health. The amount of safe drinking water has gone up around the world, but9one billion humans are still in great need10clean, drinkable water.

    March 22nd is World Water Day. It started in 1993. It not only makes us think about the importance of water, but also calls on (号召) us to 1 and protect water. Today, we're facing terrible water problems. Among them, wastewater problem is especially2. And the subject of World Water Day in 2017 is “wastewater”.

    What is wastewater? It is used water. Usually, wastewater comes from homes, 3, hospitals and so on. It is produced by different kinds of activities, including washing the machines, taking showers and using the kitchen. The rain also 4 wastewater when it is running down the street during a storm. No matter where it comes from, this kind of water is sure to have5harmful in it.

    6must we treat (处理) wastewater? Wastewater has a big influence on our life. It causes both illness for us and pollution for the environment. We must care for our environment and our own7.

    How can we treat wastewater? Different kinds of wastewater need different ways of treatment. Wastewater 8 homes can be reused. Then there will be 9 wastewater. Also, factory wastewater has to be cleaned 10 it goes back to nature.

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.