1. Listening

2. chemical fertilizer cow dung radish 用化学肥料和有机肥料的区别 :

3. Listening What is the main topic of the conversation? The possible bad effects of chemical fertilizers on the fruit and vegetables that we eat today.

4. 1.Paul thinks that Carrie is not telling him the truth. 2.Using chemical fertilizers always makes vegetables empty inside. 3.Today’s fruit is not as healthy for people as fruit fifty years ago. 4.Eating more vegetables might not always be good for us. 5.All of today’s vegetables look healthy but in fact are not. Listening T F T F T

5. WHAT’S WRONG WITH THE VEGETABLES? Girl: Hey, Paul, listen to this … a magazine article about a farmer who used too much chemical fertilizer on his fields. When his vegetables were picked, they were all found to be empty! Listening text

6. Boy: Empty? You’re joking, Carrie… that can’t be true! Girl: I didn’t believe it either! This article says this can happen sometimes with vegetables like cucumbers, carrots and pumpkins. The chemical fertilizer makes the vegetables grow fast to look big and beautiful, but they’re empty inside!

7. Boy: You know, I’ve noticed that sometimes my mum buys carrots from the supermarket that have big holes down the centre. I guess that must be from using chemical fertilizers!

8. Girl: Yeah, that’s what the magazine says! The main point of the article, though, isn’t about holes in our vegetables. It’s talking about why the fruit and vegetables we eat today aren’t as nutritious as the ones our grandparents ate.

9. Boy: What? My mum is always telling me to eat more vegetables, because they’re good for me!

10. Girl: Yeah, I know – my mother says that same thing! And it’s true – they are good for us … but the problem is that they aren’t healthy enough! All these chemical fertilizers – they kill off both the bad AND the good things in the ground. The ground doesn’t have enough vitamins and minerals any more to help crops grow healthy.

11. Boy: So… if our fruit and vegetables were grown with chemical fertilizers, they might LOOK healthy, but probably aren’t REALLY healthy? I guess we’ve got to stop using so many chemical fertilizers to grow our food!

12. Listening on Page 48

14. Do you remember the poem? 天苍苍，野茫茫，风吹草低见牛羊。 Can we see this beautiful scene again?

15. Listening Listen to the tape and tick what you hear. 1.Heat and little rain. 2.Turning forests into farmland. 3.Overusing fields to feed farm animals. 4.Using new scientific farming methods. 5.Wasting water in farms and at home. 6.Farming too much on poor land.

16. Listen to the tape again and choose the best answer to each question. 1.Why was North Africa important in the first century BC? A. Rome sent a lot of corn and wheat to North Africa. B. Land in North Africa was used to produce the bread that fed all of Rome. C. The desert in North Africa was famous in Rome.

17. 2. How does farmland turn into desert? A.Wind blows away dry soil and then the land becomes sandy. B.Hot weather makes the land become sandy. C. Too many plants can make farmland become desert.

18. 3. How are new farming methods helping to stop the desert in Xinjiang? A. The methods let the farmers use les water. B. The methods let farmers grow the same amount of crops in less land. C. The methods do not use fertilizers.

19. FIGHTING GROWING DESERTS Why do we have deserts today? Deserts have not always been here. Most deserts that we have today were once green lands full of plant life. One of today’s biggest deserts is in North Africa. However, in the 1st century BC farms in North Africa grew corn and wheat to make bread for the whole city of Rome. How did this area become desert? Listening text

20. Both weather and people can help form a desert. Hot weather or very little rain makes the land so dry that nothing can grow. If people cut down or burn trees and plants to make land clear for farming, the wind can blow the soil away and turn the dry land into sand. Another big problem is farming on land that is not very good.

21. This poor land can very quickly turn into desert, if it is farmed too much. One of the biggest causes, however, is when people take their animals to the same fields to feed over and over, and the fields finally lose all their nutrition. Because of these problems, deserts are slowly taking over green land in many parts of the world, including China.

22. However, we can fight the growing deserts! In some parts of China people are working to prevent desert from expanding. In Xinjiang, for example, some farmers are trying new scientific farming methods. These methods make it possible to use less land for crops, so farmers then can plant trees on the rest of their land!

23. One Xinjiang farmer, used only HALF of his fields to grow the SAME amount of crops as last year. On the other half of his land, he planted fruit trees. The work of people like this is helping to fight the world’s growing deserts.