Unit 6 Earth First Developing ideas 课件-2023-2024学年高中英语外研版（2019）必修第二册

外研版(2019)英语必修二 Unit 6 Earth first Developing ideas (Reading) Learning objectives 1.To have a general knowledge of what's really green in our daily life. 2.To learn the role and function of subheadings. 3.To learn some keywords and expressions in this lesson. Iead-in Pre-r eading While-reading Post-readin g Lead-in Look at the questions about“green living”and tick your answers. 1 Which shopping bag is more environmentally friendly? □ A plastic bag. □ A paper bag. √ Neither of these. 2 What should you do to save energy when leaving your home? □ Turn off a device. 力Unplug a device. □ Neither of these. 3 What food is better for the environment? □ Food produced near to where you live. √ Food produced far from where you live. □ It depends. 4 Which uses less water? □ Taking a bath. □ Taking a shower. ☑ It depends. Now work in groups and see if other people share your ideas. o Learning to learn As subheadings expand on the main heading or title,they can be slightly longer than the main heading.Although not every paragraph needs a subheading,they can be skimmed to give the reader an overall understanding of the content of a text. Pre-reading Read the four subheadings in the passage and decide if they are true or false.The n read the passage and check your answers. While-reading Skimming What's the main idea of the passage? It discusses some common“green truths” which have been shown to be half true or even completely false . When you turn off a device,it stops using power. When we turn off a device, such as television,it goes into stand-by mode. Devices in this mode still use power,and older devices in stand-by mode can use even more.This happens because electricity continues to leak from the device,even when it is turned“off”.To make sure your appliance is in fact off,remove the plug from its power supply. Paper shopping bags are better than plastic ones. Plastic bags cause litter and are a danger to wild animals,which mistake them for food.It takes hundreds of years for plastic to break down,but much less time for paper.Because of this,people think paper bags are the better environmental choice. However,making a paper bag uses four times as much energy as making a plastic bag and up to three times the amount of water. The process also produces more greenhouse gases. In fact,both kinds of bags are bad for the environment.So,take a reusable bag with you when you go shopping. It's better to take a shower than a bath. It depends on how long you spend in the shower and how large your bath is.If you spend more than eight minutes in a shower, you'll use as much water as in a bath-about 50 litres of water.Therefore,the key is to keep your shower time as short as possible. Environmental awareness is now part of daily life.But it's worth checking common ideas and opinions to see what's really green. Eating local food is good for the environment. It seems like common sense:eating local food should be better for the environment,because it does not need to betransported long distances and kept cold during transport.Unfortunately,it is not that simple.It is the production of food,not its transport,that uses most of the energy and produces most of the greenhouse gases. In some cases,local produce might have used more energy and produced more greenhouse gases than produce grown a long way away- even taking into account its transport. CAUSES 1 Making a paper bag uses more energy and water than making a plastic bag.It also produces more greenhouse gases. 2 Devices turned offgo into stand-by mode and still use power: 3 Local produce sometimes might use more energy and produce more greenhouse gases than produce grown a long way away—even taking into account its transport. 4 Ifyou spend more than eight minutes in a shower;you'll use as much water as in a bath—about 50 litres of water. EFFECTs) Paper bags are not good for the environment. Turning off a device won't stop it from using power. Eating local food isn't always better for the environment. It's not always better to take a shower than a bath. While-reading Read the effects and complete the causes of these according to the passage. 1 Which of the“green truths”surprises you most?Give your reasons. When you turn off a device,it stops using power.Usually I just turn off my television before going out,thinking it is a safe and green way.I don't know it's still a waste of energy. 2 Are you aware of any other“green truths”that are not true?Share them with the class. Bike-sharing is a green method of transportation and provides a user-friendly experience.However,it causes the energy to be wasted if the bikes are thrown away by the roadside. Post-reading Think &Share Post-reading Think &Share 3 How“green”are you?Share your“green actions”with the class. I usually try to save energy and water in my daily life.For example,I always turn off the lights when I leave a room.I walk or ride a bike instead of taking a bus or a taxi.I take a cloth bag when I go shopping. 4 What can you do to become“greener”? I can stop using the things that can be used only once.I can unplug the TV set before I go out.I can stop people from producing power from coal. Post-reading Work in groups.Give a talk about one of the“green truths”in the passage. 1 Use these questions to help plan your talk. Which“green truth”are you going to talk about? Why do people believe it is“green”? Why is it not completely true? What can you do to become“greener”? 2 Organise your talk following the steps below. Start your talk by stating the topic. Describe your chosen“green truth”in more detail. Explain why it is not completely“green” . End your talk by encouraging your audience to become“greener” . 3 Give your talk to the class. · · · · · · · · Post-reading Sample I'm going to talk about one of the“green truths”—Paper shopping bags are better than plastic ones.As we all know,plastic bags cause litter and are a danger to wild animals,which mistake them for food.It takes hundreds of years for plastic to break down,but much less time for paper. Because of this,we think paper bags are the better environmental choice. However,making a paper bag uses four times as much energy as making a plastic bag and up to three times the amount of water.The process also produces more greenhouse gases.In fact,both kinds of bags are bad for the environment.So,why not take a reusable bag to become“greener” when going shopping? Write a short passage on the topic of“ What can you do to become greener ?” using some transitional words. Post-reading Assignment $$