朗文英语听说教程1 Unit 2听力原文

Unit 2 Hew Kinds of Food

Unit 2 Hew Kinds of Food

Part 1

Teacher: Hi, everybody…how's it going? ... Good.…Has everyone turned in their homework? Allrighty, then let's get started. IF you remember, last weekwe were discussing some research in the area of genetics.Today, I'd like to talkabout something I'm sure you've allheard about-genetically modified or "GM" food.

Genetically modified food is food--either a plant or animal--that has been altered in the laboratory by scientists. The scientists take something from one plant oranimal, and add it to a different plant or animal to makeit grow in a different way. Today, we'll look at some of the benefits, and the possible risks of genetically modified fond.

Let's start with a discussion of some of the benefits ofGM food. Genetic scientists are really trying to makefood plants that are better than normal plants, to makeplants that are altered inways that make the plant grow better or taste better or be healthier to eat than normalplants.

One benefit is that genetically modified plants may needfewer pesticides than normal plants. For example, thereis a type of corn that is bad for insects--when the insectseat the corn plant, they die. However, the corn doesn'thurt people. This type of corn is beneficial because farmers use fewer pesticides to grow the corn, and so there isless pollution in the environment. Also the corn is lessexpensive because the farmers don't have to spend a lot ofmoney on pesticides. So, by using fewer pesticides, the corn is cheaper and the environment is cleaner.

Another benefit of genetically modified plants is that theymay grow better than normal plants. One example is a type of genetically modified strawberry that can grow incold weather. These are better than normal strawberriesbecause farmers can plantthe strawberries earlier in thespring and later in the fall, when normal strawberries usually die. So, as a result,

Unit 2 Hew Kinds of Food

farmers can grow many more strawberries than they used to. So that's another benefit plants that grow better.

Finally, a third benefit is that many genetically modified plants stay fresh longer after they are harvested. So, for example, there is a land of tomato that

stays fresh in the store for about two months, instead of one or two weeks. This means that there is more time to get the food to the stores andthatstores have more rime to sell the food.Less food is thrown away and wasted. So it's a great benefit to have food that stays fresh longer--and we can consume more of the food we grow.

Part 2

Teacher: Now that we've looked at some of the benefit of genetically modified plants, let's talk about the risks ofgrowing this type of food. We don't really know what theharmful effects are, but there are several things that people ate worried about.

One risk is that the genetically modified plants may start to dominate the other wild plants in the environment.This is a problem with some types of tomatoes, for example. The new tomato plants are stronger than

normal plants, and because they are stronger and grow fasterthan the wild plants, the genetically modified tomatoesmay start to dominate the environment,causing thewild plants to die. So having one plant dominate all theother plants isn’t t good for the environment.

Another risk is that genetically modified plants will hurtwild animals and insects in the environment. For example, the genetically modified corn 1 mentioned earlier hasalready caused this problem. Now some butterflies thatlive near the corn are dying--butterflies that are goodinsects, and don't eat the corn. It's possible that corn iskilling the butterflies somehow, but we're not sure. Wejust know that more butterflies are dying than normal. But clearly there's a risk that genetically modified foodscan hurt animals and insects in the environment.

Unit 2 Hew Kinds of Food

But probably the most important risk is that geneticallymodified food maybe harmful to the people who consume the food. The alterations in the plants maycause serious problems for people--we just don't know.Scientists are trying all kinds of new things, such as putting the genes from animals into a plant. For example, to make a fruit like strawberries stay fresh longer, scientists took a gene from a fish--a gene that helps the fish live incold water and put that into a strawberry. Will thatstrawberry be harmful to people? We don't know. Bur itmay be.

So it's clear that there are some important benefits to genetically modifiedfood but also some risks-risks thata lot of people aren't willing to take. So let's stop here and discuss any questions you have at this point…

1.What is genetically modified food?

a. Fresh food

b. Dangerous food

c. Altered food

2.What genetically modified fruit did the speaker mention?

a. Strawberries

b. Apples

c. Bananas

3. What is a benefit of genetically modified food?

a. It needs fewer pesticides.

b. It grows in less space.

c. It dominates the env ironment.

4. What is a risk of genetically modified food?

a. It may stay fresh longer.

b. It may be more expensive.

c. It may be harmful to people.

5. What are three benefits of genetically modified food?

Genetically modified food needs fewer pesticides. Genetically modified food/p lants grow better than normal. In addition, they stay fresh longer after they ar

e harvested.

6. What are three risks of genetically modified food?

Genetically modified food/plants may dominate other plants in the environme nt. Also, they might hurt wild animals and insects. They might even hurt the pe ople who eat them.