Listening

Situation 1 Talking about Refrigeration

Task 1

Listen to a conversation and tick the facts about refrigeration.

□ 1.Refrigeration is the process of removing heat from an enclosed space,or from a substance,to lower its temperature.

□ 2.A refrigerator is based on refrigeration.

□ 3.Refrigeration is one invention that has changed the way we conduct our daily lives.

□ 4.A refrigerator uses the evaporation of a liquid to absorb heat.

□ 5.Before refrigeration technology was developed,preserving food was a big job.

□ 6.We only use refrigeration technology to store food.

□ 7.Our happy life now owes much to the invention of refrigeration.

Task 2

Listen to the conversation again and complete the following sentences according to what you've heard.

Wang Xin: Hi,Zhang Ming!What are you doing here?

Zhang Ming: I'm here to see my aunt.How about you?

Wang Xin: I'm a student in a university in this city.

Zhang Ming: Really?What's your major?

Wang Xin: I major in 1.

Zhang Ming: Refrigeration?What's it about?

Wang Xin: Well,refrigeration is the process of 2 from an enclosed space,or from a substance,to 3 its temperature.

Zhang Ming: Is 4based on it?

Wang Xin: Yes, 5that produce refrigeration are called refrigerators.A refrigerator uses the evaporation of a liquid to absorb heat.The liquid,or 6,used in a refrigerator evaporates at an extremely low temperature,creating 7 temperatures inside the refrigerator.

Zhang Ming: So refrigeration is very important to human beings.

Wang Xin: Absolutely.Before refrigeration technology was developed, 8 was a big job.

Zhang Ming: Well,I would say refrigeration is one 9 that has changed the way we conduct our daily lives.We can preserve food more easily nowadays,so the food 10 is more stable.

Wang Xin: That's true.Our happy life now owes much to the invention of refrigeration.

Situation 2 Talking about the Purpose of Refrigeration

Task 3

Listen to a passage and answer the following questions.

1.What is the main reason for having a refrigerator?

2.What is the basic idea behind refrigeration?

3.How does the refrigerator make milk stay fresh?

4.How long can the milk last by freezing?

5.What are the most common forms of food preservation used today?

Task 4

Listen to the passage again with some blanks for you to fill in.

The fundamental reason for having a refrigerator is to 1.Cold temperatures help food stay fresh longer.The basic idea behind refrigeration is to 2 the activity of bacteria which all food contains so that it takes longer for the bacteria to 3 the food.For example,bacteria will spoil milk in two or three hours if the milk is 4 on the kitchen counter at room temperature.However,by reducing the temperature of the milk,it will 5 for a week or two—the cold temperature inside the refrigerator 6 the activity of the bacteria that much.By 7 the milk you can stop the bacteria altogether,and the milk can last for months.Refrigeration and freezing are two of the most common forms of food 8 used today.