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UNIT 7 WATER
INTRODUCTION 7.1 Study the information and answer the following questions after. Water is a very important part of our environment. But how important is it? How many ways of using water do you know? Here are some of them. DOMESTIC Drinking People need to drink clean water every day. Over 1.5 billion people do not have clean drinking water. Washing Taking a regular shower or bath is part of our lives. We also use water to wash the dishes, our clothes, and the house. The problem is, this fresh water then becomes waste water. Cooking Do you want to cook some pasta or rice? You need water! Preparing salad? You wash it in water. Boiling potatoes? Water again! The WHO (World Health Organization) says that a person needs 19litres of water a day. One in three Asians do not have safe drinking water, and one in two has no sanitation. Over 1.5billion people do not have clean drinking water. AGRICULTURE Animals Like humans, animals need to drink water to survive. Irrigation Plants need water, too. So farmers use it to help their crops to grow. With water, dry land can produce crops. When there is no rain, irrigation is necessary for agriculture. Fish Fish live in fresh water, in lakes and rivers. Many fish live in salt water, in the ocean. These fish are wild, but in many countries there are now also fish farms. INDUSTRY Machinery Machines use water. Transport We transport things by water. Ships travel on the seas, rivers and canals. Energy Countries where it rains a lot, or with high mountains, use water to produce electricity. The WHO says that the largest water users are: Agriculture 70%, Industry 20% and Domestic Use 10%. ► 1 How many ways do we use water? 2 How many ways do you use water? 3 What is WHO? 4 What is the difference / similarity between drinking water, clean water, fresh water and waste water? Use a dictionary to help you. 5 What is irrigation? Where and why is it used?
7.2 Can we live without water? Of course not. Read the text below to support this idea and answer the questions after it. The human body is about 65 per cent water. If you stopped drinking water (or drinks and food containing water) you would die within three or four days. But the water you drink must be clean. Each day an average person uses the following amounts of water: Toilet flushing 35 litres Bathing 30 litres Cooking and drinking 30 litres Using a shower 12-20 litres The average daily total per person is 140 litres. The average family uses 480 litres of water a day. Water can carry diseases. According to a recent report published by the United Nations, every day throughout the world about 25,000 people die from diseases related to dirty water. It takes 31,600 litres of water to make one car and 4,124 litres to make one tonne of steel. It takes 53 litres of water to make one pair of leather shoes and 9 litres of water to make every paper that you read. ● How much of the human body is water? ● How much water does an average person use for bathing? ● How many people die per day from disease related to dirty water? ● How many litres of water does it take to make one pair of leather shoes? ● How long can a person live without water?
7.3 Here are some words and phrases relating to water. Match them with their definitions.
7.4 Fill in the appropriate words from the list. shallow / deep / level / content / flooding / ranging / torrent / irrigate / drought / dam / amphibious 1 Many species of frogs are …….. . 2 A system of canals carries water to …….. the soil in hot countries. 3 The water …….. of the River Thames gas risen in the past few days. 4 A …….. is a special wall across a stream to stop the water from flowing. 5 Parts of coastal dam collapsed, causing serious …….. in the town. 6 Be careful! The lake is quite …….. here. 7 This river is not navigable because it’s too …….. for boats. 8 After five days of heavy rain the Telle River was a …….. . 9 Condensed milk is produced by removing about 50% of the water …….. of whole milk. 10 …….. is a long period of time when there is no rain and crops die.
7.5 Match the two parts of the sentences.
7.6 We all need water. The problem is, there’s often too much – or too little. And there are other problems, too. Let’s look at some of them.
7.7 Are these statements correct or incorrect? 1 The human body is about 65% water. 2 Fresh water lakes contain salt. 3 People can live 40 days without water. 4 Resources of river, lake and underground fresh waters are distributed unevenly on the continents. 5 The total area of lakes in Russia is larger than in Great Britain. 6 Rivers and lakes not only supply water resources, but are also used as transport systems and fisheries. 7 Dumping sewage into seas is not dangerous. 8 Today water recycling in industrial enterprises is a reality.
7.8 Read the information carefully and pay attention to the verbs in bold. When water is heated to 100°Celsius, it boils and becomes steam. When steam touches a cold surface, it condenses and becomes water again. When water is cooled below 0°Celsius, it freezes and becomes ice. If the temperature increases, the ice melts. ► To check your good memory represent the text above without looking at it.
Date: 2014-12-22; view: 2653
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