Самостійна робота. 1.Визначте, до якої частини мови відносяться наступні слова

WORD-BUILDING (Test)

1.Визначте, до якої частини мови відносяться наступні слова. Перекладіть їх

Beautiful, function, artist, musician, heartless, economic, worker, badly, act, action, active, basic, fruitless, population, movement, historic, democratic, work, daily, literature, picture, organization, friendship, highly, leader, fight, fighter, national, impressive, hopeful, hopeless, beautiful, special, specialist, define, definition, humanism, humanist, humanistic, use, useful, useless.

2. Перекладіть слова. Визначте префікс і його значення:

Coauthor, undress, disarm, postwar, illegal, unkind, reconstruct, deformation, prewar, antibody, ex-champion, superhuman, ultrashort.

3. Утворіть приметники від іменників за допомогою суфіксів: -al, -ful, -ous, -у, -able, -ible, -ic, -less, -ish. Перекладіть пари слів.

Reason, beauty, hope, doubt, care, aim, use, desire, boy, success, heart, experiment, form, office, danger, fame, electron, base, nature, cloud, sun, child, Scott, history, home.

4.Перекладіть речення. Визначте, до якої частини мови відносятьсянаступні слова. Назвіть складні слова:

1. Many pupils study English. 2. My grandfather has a large study. 3. Who ruled this country? 4. All sportsmen must obey the rules of the game.. 5. All peace-loving people work for peace for the whole of mankind.

5. Назвіть дієслова, від яких утворені наступні іменники:

Protection, show, writer, worker, movement, investigation, achievement, statement, reader, department, equipment, construction, organization, reporter, arrival, improvement, conductor, establishment, development, education, definition, regulation, assistance, agreement.

6. Пере кладіть без словника.: Визначте, до якої частини мови відносяться наступні слова

a) Specialist, institute, university, culture, central, national, nation, international, organization, minister, nature, natural, traditional, progressive, moral, social, socialist, public, programmer, popular, modern, revolution, revolutionary, final, talent, continent, festival, political, experiment, experimentation, electricity, technical, transformation, system, systematically, practice, practical, seminar, lecture, lecturer, period, historic, history, professor, complex, form, acceleration, instrument, philosopher, idea, basic, fundamental, conceptions, mass, class, element, motor, method, problem, energy, radio, text, material, temperature, progress, television.

b) 1. France and England are European countries. 2. In the evening we like to listen to classical music. 3. We saw a comedy at the Drama Theatre last night. 4. Your train leaves from platform two. 5. This jazz orchestra gave several concerts in our town. 6. In 1610 Galileo constructed the first telescope in the world. 7. This was a dangerous experiment.

7. Проан алізуйте наступні слова.Визначте їх складові. Перекладіть їх

Ice-hockey, world-wide, bedroom, newspaper, long-term, birthplace, sportsman, apple-pie, peace-loving, schoolchildren, football, highland, television, underground, north-west, sometimes, lowland, landscape, well-known, multinational, network, vice-president.

8. Поставте слово, у дужках, у відповідну форму форму.

1. My father is very... (act) even though he’s seventy. 2. I’ve always wanted to work in the theatre, but... (act) it isn’t a very secure profession. 3. I... (hope), we’ll soon find a solution to the problem. 4. Look... (care) to the left and to the right before crossing the road. 5. It was very... (care) of you to lose my watch. 6. I take two... (day) newspapers and three Sunday papers. 7. You’ve broken my camera! Look at it! It’s... (use)! 8. Thanks for the advice. It was really... (use). 9. I have some very... (noise) neighbours. 10. She became... (fame) as a result of her invention.

Text 1. Read the article, translate it, write down all the unknown words for you, learn them and express the main idea of the article.

Ice Shelves Melting Away

The breaking up of ice shelves is a spectacular indicator of climatic change. Observations around the Antarctic peninsular have revealed a pattern of gradual retreat of the ice, associated with regional atmospheric warming, increased summer

melting and fracturing of the ice shelves over the last forty years.

Scientists of the British Antarctic Survey have examined the break-up of the northern sections of two Antarctic shelves in order to discover the criteria for the stability of the ice shelves, and have discovered deformation patterns which reveal the stability of the ice shell This research suggests that one ice shell known as Larsen B could begin an irreversible collapse if the ice retreats only a few kilometres.

Unit 3

Text 1 Read and translate the text pay attention to the new words. Contextualize them

Air Pollution

Air pollution occurs when the concentrations of certain substances become high enough to cause the atmospheric environment to become toxic. Air pollutants can be gaseous, liquid or solid in form, and can come from natural as well as human sources. Examples of natural sources of air pollution include forest fires, pollen, volcanic emissions, and dust. Human sources of air pollutants include emissions from industry, agriculture, forestry, transportation, power generation, and space heating.

Air pollution can threaten the health of human beings, trees, lakes, crops, and animals. Abundant amounts of air pollution changes natural atmospheric processes, causing acid rains, ozone hole, and enhancing greenhouse effect. Additionally, it causes economic losses.

Pollutants are classified either as primary pollutants, or those that enter the atmosphere directly from various sources, or as secondary pollutants, or those that are formed when primary pollutants react with each other or with other compounds present in the atmosphere.

Industrial or gray smog is considered the most serious type of air pollution. Smoke and oxides of that are released by burning coal and oil containing minor amounts of sulfur is the cause. The smoke gives the air a gray color. Industrial smog has been known to cause air pollution disasters. One of the worst occurred in London in December of 1952. Five days of stagnant air brought about high-pressure systems caused between 3,500 and 4,000 deaths.

Another main cause of air pollution is exhaust fumes from cars and other vehicles that run on gasoline or diesel. Until a few years ago, lead was added to most gasolines to make car engines run better. The lead passes through the engine and out of the exhaust system into the air. Lead is a highly toxic metal and can cause nervous system damage and digestive problems.

Road traffic emissions, particularly from diesel vehicles are a major source of particulate matters and nitrogen oxides. PM10 particles (the fraction of particulate in air of very small size (<10 µm)) are of major current concern, as they are small enough to penetrate deep into the lungs and so potentially pose significant health risks. Particles are often classed as either primary or secondary pollutants.

Sulfur and nitrogen oxides (primary pollutants) from power plants, industry, cars and other sources cause rain, snow and fog to become acidic. The most serious damage caused by acid rain today is acidification of water lakes and rivers. In some cases they become so acidic that they can no longer support fish and their food chains. Forest health can also be affected from this in areas where the soils are being acidified.

Ozone depletion is another result of pollution. The ozone layer in the stratosphere protects the earth from harmful ultraviolet radiation from the sun. Release of chlorofluorocarbons (CFC's) from aerosol sprays, polystyrene containers, refrigerator coolant and air conditioning units removes some of the ozone, causing "holes"; to open up in this layer and allowing the radiation to reach the earth.

Ozone in the in the upper level occurs naturally and protects life on earth but ozone at ground level is a noxious pollutant. It is the major component of photochemical smog (also know as brown smog) and presents the most intractable urban air quality problem. Ozone is not emitted directly. It is secondary pollutant formed in the atmosphere through a complex set of chemical reactions involving hydrocarbons, oxides of nitrogen, and sunlight. The rate at which the reactions proceed is related to both temperature and intensity of the sunlight.

The greenhouse effect, also referred to as global warming, is generally believed to come from the build up of carbon dioxide (CO2) gas in the atmosphere. Carbon dioxide is produced when fuels are burned. Plants convert carbon dioxide back to oxygen, but the release of carbon dioxide from human activities is higher than the world's plants can process. The situation is made worse since many of the earth's forests are being removed, and plant life is being damaged by acid rain.

Finally, air pollution can also occur indoors. Common indoor air pollutants include carbon monoxide and nitrogen dioxide from faulty gas heaters and cookers, carbon monoxide and benzene from cigarette smoke, and volatile organic compounds (VOCs) from synthetic furnishings, vinyl flooring and paints. In addition, there are biological pollutants such as dust mites and mould.

Adequate ventilation is a key to controlling exposure to indoor air pollution. Home and work environments should be monitored for adequate airflow and proper exhaust systems installed.

Air pollution generates various economic losses but their detailed estimation is extremely difficult. They may be divided into four groups: expenses for air quality protection; expenses generated by the worse health condition of the society; losses of raw materials which become air pollution; losses caused by the increased corrosion of machines, buildings, and damage of historical buildings and monuments.

The problem of air pollution is worldwide and transcends national boundaries. Though air pollution is still a serious problem, in many countries in the world, steps are being taken to stop the damage to our environment from air pollution. Many electric power plants, factories, and facilities that burn wastes are equipped with devices called scrubbers. Scrubbers remove sulfur dioxide and other pollutants before the wastes are released into the air. Also, today's cars are designed to create less pollution. Many are equipped with anti-pollution devices called catalytic converters, which reduce the amount of pollution from automobile engines.

Vocabulary

to occur – виникати, мати місце

gaseous ['gæsɪəs], ['geɪʃəs] - газовий

pollen - пилок

emission - викид

power generation – виробництво електроенергії

to threaten - загрожувати

ozone hole - озонова діра

to enhance [ɪn'hɑːn(t)s], - збільшувати

greenhouse effect - парниковий ефект

economic losses – економічні втрати

compound – хімічні сполуки

oxide ['ɔksaɪd] - хім. окис

sulfur (sulphur) ['sʌlfə] - сірка

stagnant ['stægnənt] - застійний

high-pressure – високий тиск

to exhaust - випускати

fume – газ, дим

gasoline ['gæs(ə)li:n] - ам. бензин

lead - олово

digestive [daɪ'ʤestɪv] - травний

particulate matter – мікроскопічна частка, що спричиняє забруднення навколишнього середовища

nitrogen ['naɪtrəʤən] -. азот;

fraction - частка

to penetrate – проникати всередину

to pose - являтися (проблемою)

particle - частка

power plant (US FOR power station) - електростанція

acidification [ə/sɪdɪfɪ'keɪʃən] - окислення

food chain – ланцюг харчування

depletion [dɪ'pli:ʃ(ə)n] - виснаження

ozone layer - озоновий шар

polystyrene (US USUALLY TRADEMARK Styrofoam) [/pɔlɪ'staɪri:n] – полістірол

unit - тех. елемент,

noxious ['nɔkʃəs] - шкідливий

intractable [ɪn'træktəbl] - неподатливий

hydrocarbon [/haɪdrəu'kɑːb(ə)n] - вуглеводень

to proceed – продовжувати, виходити з,переходити

carbon dioxide (CO2) [daɪ'ɔksaɪd] - вуглекислота

to process - обробляти

carbon monoxide (CO) ['kɑːbənmɔ'nɔksaɪd]-- окисел вуглецю

faulty - несправний

benzene ['benzi:n] - бензол

volatile ['vɔlətaɪl] – летючий, той що швидко випаровується

furnishings - меблювання

vinyl ['vaɪn(ə)l] – вініл

mite - внесок

mould - пліснява

scrubber – газопромивник, скребок

sulfur dioxide (SO2) – двоокис сірки

EXERCISE 1 Fill the gaps in the sentences, using the words and phrases below:

noxious pollutant; particulate matters; photochemical smog; volatile organic compounds; lead; disasters; gaseous, liquid or solid; oxides of nitrogen; fuels; smog; wastes; air pollution; ozone depletion; sulfur and nitrogen oxides; dust mites and mould; greenhouse effect; acidification; carbon dioxide; indoors; sulfur; exhaust fumes; to penetrate; economic losses

1…. occurs when the concentrations of certain substances become high enough to cause the atmospheric environment to become toxic.

2.Air pollutants can be …. in form, and can come from natural as well as human sources.

3.Abundant amounts of air pollution changes natural atmospheric processes, causing acid rains, ozone hole, and enhancing …

4.Industrial or gray … is considered the most serious type of air pollution.

5.Smoke and oxides that are released by burning coal and oil containing minor amounts of …is the cause.

6.Industrial smog has been known to cause air pollution ….

7.Another main cause of air pollution is ….from cars and other vehicles that run on gasoline or diesel.

8.Until a few years ago, … was added to most gasolines to make car engines run better.

9.Road traffic emissions, particularly from diesel vehicles are a major source of …. and nitrogen oxides.

10.PM10 particles are of major current concern, as they are small enough ….. deep into the lungs and so potentially pose significant health risks.

11….. from power plants, industry, cars and other sources cause rain, snow and fog to become acidic.

12.The most serious damage caused by acid rain today is of water lakes and rivers.

13…… is another result of pollution.

14.Ozone in the in the upper level occurs naturally and protects life on earth but ozone at ground level is a …..

15.Ozone is the major component of ….. and presents the most intractable urban air quality problem.

16.Ozone is secondary pollutant formed in the atmosphere through a complex set of chemical reactions involving hydrocarbons,…., and sunlight.

17.The greenhouse effect, also referred to as global warming, is generally believed to come from the build up of ……. gas in the atmosphere.

18.It is the major component of ….. are burned.

19.Plants convert carbon dioxide back to …., but the release of carbon dioxide from human activities is higher than the world's plants can process.

20.Finally, air pollution can also occur. …

21.Common indoor air pollutants include carbon monoxide and nitrogen dioxide from faulty gas heaters and cookers, carbon monoxide and benzene from cigarette smoke, and ….. from synthetic furnishings, vinyl flooring and paints.

22.In addition, there are biological pollutants such as ….

23.Air pollution generates various ….. but their detailed estimation is extremely difficult.

24.Many electric power plants, factories, and facilities that burn ….. are equipped with devices called scrubbers.

EXERCISE 2. Translate from Ukrainian into English.

1. Шкідливі відходи отруююють наші річки. 2. Сірчистий газ—один з багатьох забруднювачів, які випускаються в повітря електростанціями на вугіллі. 3. Пар це вода в газоподібній формі. 4. Плутоній це пальне, яке використовується для вироблення ядерної енергії. 5. Світло не проникає через туман. 6. Комп’ютери обробляють дані. 7. Забруднення повітря призводить до виснаження озонового шару. 8.Місту загрожує епідемія. 9. Заводи повинні контролювати викиди. 10. Білки, видно, є найбільш складні хімічні сполуки.

Read the text and say what the main idea of this text is

Climate change impact on food prices and hunger

Many scientists believe that impact that climate change will have on hunger and global food prices will be quite large in years to come. The latest study by new Stanford University has also concluded that that higher temperatures could significantly reduce yields of wheat, rice and maize in the next 20 years, and such scenario would likely cause food prices to rise substantially which will in the end result in global increase in number of poor people that will struggle to survive.

However we must look this problem from more than just one dimension. To many of us the most logical thing seems the conclusion that if food prices are about to increase, this will automatically increase the amount of poverty in the world as poor people will have to spend a lot more money on food. This is true for some people but it cannot be applied to all people because "poor people category" has many different subcategories including people who farm their own land and they would for instance be actually benefiting from higher crop prices. The most affected will be definitely poor people that live in cities.

This study has come up with the three possible scenarios. According to the first scenario if global temperatures will rise 1.8 degrees Fahrenheit (1 degree Celsius) by 2030 then there will be relatively little change in crop yields, food prices and poverty rates.

Second scenario that includes temperatures increase by 2.7 F by 2030 is likely to cause a 10 to 20 percent drop in agricultural productivity, which will result in a 10 to 60 percent rise in the price of rice, wheat and maize, and the overall poverty rate will rise about three percent.

Under the third scenario in which global temperatures rise just 0.9 F (0.5 C), crop productivity would actually be increased, and there would be even surplus in food that could lead to a 16 percent drop in food prices.

Many scientists believe that the most likely of these three scenarios is the first scenario so in the next 20 years there should be no significant change in food prices and poverty. But if we continue with excessive carbon emissions we will not be able to avoid increase in food prices and global poverty because higher temperatures will significantly decrease the agricultural productivity, and food prices could skyrocket.

Therefore the world must do everything in its power to halt the further strengthening of climate change impact because otherwise poverty will rule the world. Even today there are around billion hungry people in the world, and unless we do something about climate change this big number will soon become lot bigger.

The Passive Voice

Present simple

passive subject	'to be'	past participle
Paper	is	made	from wood
Tigers	are	found	in India

Past simple

passive subject	'to be'	past participle
The bridge opened in	was	opened	in 1977
The pyramids	were	built	by the Egyptians

Future simple

passive subject	'to be'	past participle
The novel	will be	written	tomorrow

EXERCISE 1 Complete the sentences using the given words as in the model:

Model hear

The music at the party was very loud and __________ from far away.

The music at the party was very loud and WAS HEARD from far away.

Arrest, wake, knock, check translate, find, drive, make, spend carry.

1. A decision will not _______________ until the next meeting.

2. That old building was dangerous. So it ___________ down.

3. When you go through customs, you luggage ___________ by the customs officer.

4. In the morning I _____________ by my alarm clock.

5. Next year her new book ______________ into a number of foreign languages.

6. John kicked a policeman, so he ____________.

7. After a long search the missing boy _____________ in the forest near the town.

8. Many people think that today too much money ________________ on arms. (arms - зд. оружие.)

9. The injured man couldn't walk, so he _____________ by the hospital orderlies.

10. I don't mind driving but I like when I _______________ by other people.

EXERCISE 2. Open the brackets using the verbs in Present, Past or Future Simple Passive.

1. Bread (to eat) every day. 2. The letter (to receive) yesterday. 3. Nick (to send) to Moscow next week. 4. I (to ask) at the lesson yesterday. 5.1 (to give) a very interesting book at the library last Friday. 6. Many houses (to build) in our town every year. 7. This work (to do) tomorrow. 8. This text (to translate) at the last lesson. 9. These trees (to plant) last autumn. 10. Many interesting games always (to play) at our PT lessons. 11. This bone (to give) to my dog tomorrow. 12. We (to invite) to a concert last Saturday. 13. My question (to answer) yesterday. 14. Hockey (to play) in winter. 15. Mushrooms (to gather) in autumn. 16. Many houses (to burn) during the Great Fire of London. 17. His new book (to finish) next year. 18. Flowers (to sell) in shops and in the streets. 19. St. Petersburg (to found) in 1703.

EXERCISE 3. Open the brackets using the correct tense form

1. The porter will (bring, be brought) your luggage to your room. 2. Your luggage will (bring, be brought) up in the lift. 3. You may (leave, be left) your hat and coat in the cloak-room downstairs. 4. They can (leave, be left) the key with the clerk downstairs. 5. From the station they will (take, be taken) straight to the hotel. 6. Tomorrow he will (take, be taken) them to the Russian Museum. 7. At the station they will (meet, be met) by a man from the travel bureau. 8. She will (meet, be met) them in the hall upstairs.

EXERCISE 4 Turn the following into the Passive Voice.

E.g. We often speak about her. — She is often spoken about.

1. We thought about our friend all the time. 2. The doctor will operate on him in a week. 3. The teacher sent for the pupil's parents. 4. They looked for the newspaper everywhere. 5. Nobody slept in the bed. 6. The neighbour asked for the telegram. 7. Everybody listened to the lecturer with great attention. 8. The senior students laughed at the freshman. 9. The group spoke to the headmistress yesterday. 10. The young mothers looked after their babies with great care. 11. Nobody lived in that old house. 12. They sent for Jim and told him to prepare a report on that subject.

EXERCISE 5 Open the brackets using the Passive or Active Voices.

1. Nobody (to see) him yesterday. 2. The telegram (to receive) tomorrow. 3. He (to give) me this book next week. 4. The answer to this question can (to find) in the encyclopedia. 5. We (to show) the historical monuments of the capital to the delegation. 6. You can (to find) interesting information about the life in the USA in this book. 7. Budapest (to divide) by the Danube into two parts: Buda and Pest. 8. Yuri Dolgoruki (to found) Moscow in 1147. 9. Moscow University (to found) by Lomonosov. 10. We (to call) Zhukovski the father of Russian aviation.

EXERCISE 6 Turn the following into the Passive Voice.

I. The students greeted the famous lecturer warmly.2 We asked him about his holidays. 3We received this letter after his departure. 4They often speak about him.. 5I did not leave the window open

EXERCISE 7 Change the following sentences into the Passive Voice.

A using the Indefinite Tenses (give two forms where possible).

Example: Tom gave her a book. — She was given a book. The book was given to her.

1. He broke my watch. 2. The teacher explained the rule to the students. 3. He often asks me to help them. 4. They usually do written exercises in class. 5. She will make a new discovery soon. 6. Steve will make a report at the conference. 7» They play tennis all year round, 8. His friends never forgave his betrayal, 9, The manager offers me several jobs. 10. They will promise you much, but don't imagine they will give you everything. 11. His parents regularly sent him parcels with fruit from their garden. 12. They will give me a leave in July if there is no urgent work. 13. The Spanish government offered Columbus three ships, 14. They usually send their children to camp for summer. 15. The officer charged him with a very important mission, 16, I'm sure we'll settle the matter easily. 17. The policeman fined the driver for exceeding the speed limit 18. Somebody calls her every day. 19. We request the passengers leaving for London to register. 20. The manager will sign contracts tomorrow.

В using the Indefinite Tenses (pay attention to pre­positions),

Example: She looks after him well. — He is well looked after (by her).

1. We sent for the police. 2, They speak much about this book. 3. They often laugh at him. 4. They listened to our conversation very attentively. 5.1 think they will wait for us only in a week. 6. Nobody took notice of his late arrival. 7. We looked through all the advertisements very

attentively. 8, He was a brilliant speaker, and whenever he spoke, the audience listened to him with great attention, 9. They will look after him in hospital much better. 10. Everybody looked at her new dress with interest. 11. She sent them for a taxi. 12. People will talk much about the successful performance of the young actress. 13, They always make fun of him. 14. The teacher pointed out gross mistakes in the translation. 15. He referred to very interesting plans. 16. They agreed upon Monday as the most suitable day. 17. He did not touch upon this question unfortunately. 18. They spoke to him about his promotion yesterday

Самостійна робота

Read the article, translate it, write down all the unknown words for you, learn them and express the main idea of the article.

Acid Rain

"Acid rain" is a broad term referring to a mixture of wet and dry deposition (deposited material) from the atmosphere containing higher than normal amounts of nitric and sulfuric acids. The precursors, or chemical forerunners, of acid rain formation result from both natural sources, such as volcanoes and decaying vegetation, and man-made sources, primarily emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) resulting from fossil fuel combustion. In the United States, roughly 2/3 of all SO2 and 1/4 of all NOx come from electric power generation that relies on burning fossil fuels, like coal. Acid rain occurs when these gases react in the atmosphere with water, oxygen, and other chemicals to form various acidic compounds. The result is a mild solution of sulfuric acid and nitric acid. When sulfur dioxide and nitrogen oxides are released from power plants and other sources, prevailing winds blow these compounds across state and national borders, sometimes over hundreds of miles.

Wet Deposition

Wet deposition refers to acidic rain, fog, and snow. If the acid chemicals in the air are blown into areas where the weather is wet, the acids can fall to the ground in the form of rain, snow, fog, or mist. As this acidic water flows over and through the ground, it affects a variety of plants and animals. The strength of the effects depends on several factors, including how acidic the water is; the chemistry and buffering capacity of the soils involved; and the types of fish, trees, and other living things that rely on the water.

Dry Deposition

In areas where the weather is dry, the acid chemicals may become incorporated into dust or smoke and fall to the ground through dry deposition, sticking to the ground, buildings, homes, cars, and trees. Dry deposited gases and particles can be washed from these surfaces by rainstorms, leading to increased runoff. This runoff water makes the resulting mixture more acidic. About half of the acidity in the atmosphere falls back to earth through dry deposition.

Acid rain causes acidification of lakes and streams and contributes to the damage of trees at high elevations (for example, red spruce trees above 2,000 feet) and many sensitive forest soils. In addition, acid rain accelerates the decay of building materials and paints, including irreplaceable buildings, statues, and sculptures that are part of our nation's cultural heritage. Prior to falling to the earth, sulfur dioxide (SO2) and nitrogen oxide (NOx) gases and their particulate matter derivatives—sulfates and nitrates—contribute to visibility degradation and harm public health.

Some of the problems attributed to acid rain include:

Trees lose some of the protection in their leaves, leaving them more at risk from frost and diseases.

Tree roots may also become stunted, so they can't take up as many nutrients.

Soils lose some of their nutrients.

Increasing acid levels may cause problems for aquatic animals and plants. Some fish may have trouble breathing for example.

Acid rain may dissolve the stonework and mortar of buildings causing structural problems of buildings.

Unit 4

Text 1 Read and translate the text pay attention to the new words. Contextualize them

Water Pollution

Water pollution occurs mostly, when people overload the water environment such as streams, lakes, underground water, bays or seas with wastes or substances harmful to living beings.

Water is necessary for life. All organisms contain it, some drink it and some live in it. Plants and animals require water that is moderately pure, and they cannot survive, if water contains toxic chemicals or harmful microorganisms. Water pollution kills large quantity of fish, birds, and other animals, in some cases killing everything in an affected area.

Pollution makes streams, lakes, and coastal waters unpleasant to swim in or to have a rest. Fish and shellfish harvested from polluted waters may be unsafe to eat. People who polluted water can become ill, if they drink polluted water for a long time, it may develop cancer or hurt their future children.

The major water pollutants are chemical, biological, and physical materials that lessen the water quality. Pollutants can be separated into several different classes:

The first class is petroleum products: oil, fuel, lubrication, plastics. The petroleum products get into water by accidental spills from ships, tanker trucks and when there are leaks from underground storage tanks. Many petroleum products are poisonous for animals. Spilled oil damages the feathers of birds and the fur of animals, often it causes death.

The second class is pesticides and herbicides. There are chemicals used to kill harmful animals and plants. If they penetrate into streams, rivers, lakes, these chemicals can be very dangerous. The chemicals can remain dangerous for a long time. When an animal eats a plant that's been treated with it, the poisons are absorbed into the tissues and organs of the animals.

When other animals feed on a contaminated animal, the chemicals are passed up to them. As it goes up through the food chain, the chemical becomes more harmful, so animals at the top of the food chains may suffer cancers, reproductive problems, and death. Nitrates can cause a lethal form of anemia in infants.

The third class are heavy metals, such as, mercury, selenium, uranium, radium, cesium, etc. They get into the water from industries, automobile exhausts, mines, and natural soil. Heavy metals also become more harmful as they follow the food chain. They accumulate in living being's cells and when they reach high levels of concentration in the organism, they can be extremely poisonous, or can result in long-term health problems. They can sometimes cause liver and kidney damage.

The fourth class is fertilizers and other nutrients used to promote plant growth on farms and in gardens.

The fifth class is infectious organisms and pathogens. They enter water through sewage, storm drains, runoff from farms, etc.

The last one is thermal pollution. Water is often taken from rivers, lakes or seas to be used in factories and power plants. The water is usually returned to the source warmer than when it was taken. Even a small temperature change in a body of water can drive away the fish and other species that were originally there, and attract other species in place of them. It breaks a balance and can cause serious circumstances in future.

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