高中英语上外版（2020）必修 第二册Unit 3 Food优质第三课时学案设计

高中英语 上教版 高一年级 必修二

第三单元 Progress？第三课时（教师版）

课题：Reading and interaction: Going global (III): Vocabulary

课时学习目标：

         识别并学习文本中数量变化描述类词汇；

         掌握文本中重点词汇和词块的用法并在语境中恰当运用。

I. Language study

1. How does the writer describe the change in the world population and in the number of languages? Find out the related sentences in the passage. Underline the verbs that are used to talk about statistics.

However, since then the population has continued to increase at an alarming rate.

At that time, there were only five million humans, but this figure quickly doubled.

The population reached a billion in 1805, and since then it has multiplied seven times.

There are around seven thousand languages in use today, but the number is decreasing fast.

Experts think that the number of different languages will halve to just 3,500 by the end of this century. 

 Match the underlined verbs with their definitions below.

（1）to reduce something by a half ---------------------------------------------------- __halve___

（2）to become twice as much or as many as -----------------------------------------__double__

（3）to become smaller in number or size -------------------------------------------- __decrease__

（4）to increase by a large number or amount ----------------------------------------__multiply__

（5）to become or make something greater in number, amount, value, etc. ------__increase__

         halve  v.

         halve the price / cost

to reduce the price or cost by a half

         halve an apple

to divide an apple in half

         at an alarming rate   at a surprising and worrying speed

Over the last century, the global temperature has been rising___at an alarming rate_________.

The last few decades have witnessed _an alarming increase__ in obesity. (肥胖症病例惊人的增加)

To be exact, the number of people suffering obesity in 1975 is 11 million, and by 2016 it _had multiplied over ten times_____ . (增至十倍多)

According to the picture, which country has the highest obesity rate? 

Obviously, America tops the list with an obesity rate of 33.8%.

         a high / low rate of unemployment     高 / 低失业率

         birth / death rate     出生 / 死亡率

If the world population continues to increase at the current rate, we may face ...

rising unemployment rate          food shortage            resource crisis

and eventually, the extinction of many species.

If the world population continues to increase at the current rate, we may face the extinction of many species.

Many species are being threatened with extinction because of human population growth.

         threaten  v.  to be a danger to something  对……构成威胁

         threaten to do ... / that ...   威胁做……

         threaten ... with ... / ... be threatened with / by ...    用……威胁……

With AI technology advancing at an alarming rate, some experts are afraid that these machines may _threaten to make more people jobless__.

/ ... some experts are afraid that more people _may be threatened with unemployment___.

Will the advances in AI be a blessing or a threat?

         threat  n.  a person or thing that is likely to cause trouble, danger, etc.  威胁

         be under threat from ...        受到来自……的威胁

         pose a serious / real / potential / major threat to ...    

Some fear the advances in AI may _pose a major threat to__ their jobs.

Many species are threatened with extinction.

Many species are in danger of extinction.

         be threatened with extinction = be in danger of extinction   面临灭绝的危险

人们认为许多动植物物种由于人类活动而面临灭绝的危险，而动植物的灭绝反过来正威胁着地球的存亡。

It is believed that many species of plants and animals are in danger of extinction because of human activities, and the extinction of animals and plants in turn is threatening the survival of the earth.

         extinct  adj.  (esp of a type of animal, etc) no longer in existence  灭绝的

Many languages around the world _have become / been extinct__ (灭绝了) in the past few decades, and some believe it is largely due to globalization.

It is to a large extent due to globalization.

         to a large / great extent = to a large / great degree  在很大程度上

         to some extent / degree   在一定程度上

By _encouraging people to follow a balanced diet__, health experts are hoping to reduce the cases of obesity to some extent.

By putting a ban on single-use plastics, the government is expecting to _ease the pressure on the environment to some extent___.

By choosing food based on its carbon footprint, we can __make a difference to the environment to a large extent___.

II. More practice about language use.

1. Finish Exercise 2 on page 47.

2. Look at the bar chart showing the estimated packaging waste growth in China caused by online food delivery services. Write a short passage to describe it. Your writing should include the trend and statistics. You should also discuss the impact of packaging waste growth on the environment. Use as many words and expressions learned in this class as possible.

With the rise of online food delivery services in China, the past few years have witnessed an alarming increase in packaging waste. According to the bar chart, China contributed 0.18 million tons of packaging waste in 2015, and by the year 2017 it had multiplied almost nine times to 1.6 million tons. This figure nearly doubled in the following year.

    Food packaging usually consists of single-use plastics including containers, tableware and plastic bags. As is known, marine plastic pollution poses a major threat to coastal ecosystem. Scientists worry if the packaging waste continues to grow at the current rate, many marine species will become extinct in the future. By turning to recyclable packaging materials and reducing the use of disposable chopsticks and spoons, we are saving the future of human race to a large extent.

(For reference)

III. Interaction

In a group, share your short passage with each other. Collect the sentences with the words and expressions learned in this class, see if they are used appropriately and make necessary improvements.

IV. Assignments

1. Further improve the short passage done in class.

2. Finish Exercise 1 on page 26 and Exercise 5 / 1, 2 on page 28 in the workbook.