Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks
Water is necessary for life. People can live only a few days (44)........  it. Yet nearly 25 million   people die each year because of it. Both industrial nations and less-developed countries are worried about the (45).................... and quantity of water in the world.
Even though people, animals, agriculture, and industry use a lot of water, there is more than enough on the Earth. Water covers about three-fourths of the Earth's surface. However, 97.4 percent of it is salt water. Three-fourths of the Earth's fresh water is frozen in glaciers and in the great polar ice caps. Most of the water we use (46)................     from rivers, lakes, and the atmosphere. Less than one percent of the Earth's water is usable, and we use it over and over again.
One of the (47)......... about water is distribution. Water is not always distributed where the large (48)..........centers are. Some regions get enough rain, but it is all in one or two short rainy seasons.

(46)................................

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:
Did you ever watch a video on the Internet? Maybe you used YouTube. YouTube is a Website where people can share their video. Today, YouTube is an important part of the Internet. However, that wasn’t always true.
YouTube started with a young man named Jawed Karim and two friends. One day, Karim was on the Internet. He wanted information about the 2004 tsunami in Southeast Asia. He found news stories about it, but he couldn't find any videos. This gave Karin an idea. He wanted to help people put video on the Internet. Karim told his friends about this idea. Together, they created a company - YouTube.
YouTube become a global success. Millions of people around the world Visited the Website. It was clear to Google, another Internet company, that YouTube had a lot of value. Google made a deal. It bought YouTube for $1.65 billion. As a result, YouTube investors and its employees made a lot of money. The three friends who started YouTube were very big investors. Therefore, they made an enormous amount of money.
Karim became very rich, and he continued to work toward his PhD. There was something else he wanted to do. He wanted to help young people go into business. He used money and experience to start a new company called Youniversity Ventures. This company helps young people who have good business ideas. It gives them advice and money to start Internet businesses. Milo is one business that students started with the help of Youniversity Ventures.
Milo is a shopping Website. It helps people find products in stores near their homes. Another example is AirBoB. This Web site helps people find for video conferences. People in different places can use this site to have business meetings.
Karim has some advice for students who want to start business. First, find a successful company. Do a lot of research about the company and the top people in the company. There, copy the way they do things. For students who wants to start Interner business, Karim is probably a very good example to copy. 

Which of the following in NOT mentioned about Karim?

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions.
For hundreds of years, giving flowers have been a social means of communication. In the United States, flowers are often given during rites of passage, for commemorating special occasions or as a heartfelt gift between loved ones and friends. Flower gifting also occurs in most countries around the world. However, the meanings and traditions often vary.
While students traditionally gave their favorite teacher an apple in past years, in China, teachers are given flowers. Peonies are by far the  flower most often  given  in  China. They are also quite popularly used for weddings. Strangely, potted plants are not considered a pleasant gift among Asian cultures. The people believe that like a plant confined by a pot, the gift  symbolizes a binding or restriction.
In Russia, in lieu of giving birthday presents, the guest of honor receives a single flower or an unwrapped bouquet. Floral arrangements or baskets are not given. Russians celebrate a holiday known as Woman's Day. Traditional gifts include red roses, hyacinths or tulips. When   there is a funeral or other occasion where someone wishes to express sympathy, carnations, lilies or roses are given in circular configurations, which signify the transition of birth, life and death to   rebirth. In this instance, the color of choice is commonly yellow. For joyous occasions, arrangements and bouquets generally contain an odd number of flowers.
In the times of ancient Rome, brides carried flowers to scare away evil spirits and encourage fertility. The Dutch believed that flowers were food for the soul. When invited to someone's home in Great Britain, it is tradition to bring a gift of flowers. All types are acceptable except white lilies, which are usually seen at funerals. Unlike the United States, red roses are a symbol of love.
Flowers are generally gifted in odd numbered increments regardless of the occasion. However, the Brits also have superstitions regarding the number 13, so the number is avoided.
In the southern region of the continent, flowers are traditionally given during Christmas. Egyptians are much more conservative and restrict flower gifting to funerals and weddings. While certain flowers may have significant meanings for some, flowers in Las Vegas and across the United States flowers are an accepted gift for any reason desired.

In which country should not people bring white lilies to other houses?

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:
It can be shown in facts and figures that cycling is the cheapest, most convenient, and most environmentally desirable term of transport in towns, but such cold calculations do not mean much on a frosty winter morning. The real appeal of cycling is that it is so enjoyable. It has none of the difficulties and tensions of other ways of traveling so you are more cheerful after a ride, even though the rush hour.
The first thing a non-cyclist says to you is: "But isn't it terribly dangerous?" It would be foolish to deny the danger of sharing the road with motor vehicles and it must be admitted that there are an alarming number of accidents involving cyclists. However, although police records indicate that the car driver is often to blame, the answer lies with the cyclist. It is possible to ride in such a way as to reduce risks to a minimum.
If you decide to join the thousands in Britain who are now returning to cycling as a cheap, satisfying form of transport your first problem will be trying to decide what bike to buy. Here are three simple rules for buying a bike:
Always buy the best you can afford. Of course there has to be a meeting point between what you would really like and economic reality, but aim as high as you can and you will get the benefit not only when you ride but also if you want to sell. Well-made bikes keep the value very well. And don't forget to include in your calculations the fact that you'll begin saving money on fares and petrol the minute you leave the shop.
Get the best frame, the main structure of the bicycle, for your money as you can. Cheap brakes, wheels or gears can easily be replaced by more expensive ones, but the frame sets the    upper limit on any transformation. You should allow for the possibility our cycling ambitions will grow with practice. When you begin, the four miles to work may the most you ever dream of, but after a few months a Sunday ride into the country begins to look more and more desirable. The best thing is to buy a bike just a little bit better than you think you'll need, and then grow into it. Otherwise, try to get a model that can be improved.
The fit is vital. Handlebars and seat height can be adjusted but you must get the right sized frame. On the whole it is best to get the largest size you can manage. Frame sizes are measured in inches and the usual adult range is from 21 inches to 25 inches, though extreme sizes outside those measurements can be found. Some people say if you take four inches off from your inside leg measurement you will end up with the right size of bike. The basic principle though is that you should be able to stand with legs either side of the crossbar (the bar that goes from the handlebars to the seat) with both feet comfortably flat on the ground.

The phrase "coliel callziantions" inparagraph 2 canbest be replacedby     .

Choose the letter A, B, C or D to answer these following questions.

"Most of us are interested in one kind of sport or another, even if we don't go in for it actively. Lots of people take up a particular sport at an early age, for example tennis, skiing, or ice-skating. If they get up to a suitably high standard, they may go in for local competitions or even championships. But special training is hard work and most young people don't keep it up. Many of them opt out when they come up against tough competition.

To become a professional in any sport, you have to go through with a strict training schedule. And it's not easy! It means doing without some of life's little pleasures, too. For example, to build up your physical strength you may have to stick to a special diet and give up some of your favorite foods. Smoking and alcohol are out, and to keep fit you have to work out regularly every day.

Sometimes it all pays off, but the road to success is long and there are no guarantees. No wonder that countless young talents decide to settle for a regular job instead, and, as far as professional sport is concerned, for looking on as spectators."

2: According to the passage, which of the following statements is TRUE about special training?

Read the following passage and choose the best answer for each blank.

The General Certificate of Secondary Education or the GCSE examinations for (26) _____ are the standard school-leaver qualifications taken by (27) _____ all UK students in the May and June following their 16th birthday. If you come to a UK (28) _____ school before you (29) _____ the age of 16, you will study towards GCSE examinations in up to 12 subjects. Some subjects are compulsory, including English arid mathematics, and you can select (30) _____, such as music, drama, geography and history from a series of options. GCSEs provide a good all-round education (31) _____ you can build on at college and eventually at university. AS- and A-levels are taken after GCSEs. They are the UK qualifications most (32) _____ accepted for entry to university and are available in subjects from the humanities, arts, sciences and social sciences as well as in (33) _____ subjects such as engineering, and leisure and tourism. You can study up to four subjects at (34) _____ same time for two years, (35) _____ AS-level examinations at the end of your first year (called the lower-sixth) and A-level qualifications at the end of your second year (called the upper-sixth).

(28) _____

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks.
                   The texting pigeons
Not everybody recognizes the benefits of new developments in communnicatons technology. Indeed, some people fear that text messaging may actually be having a negative (11).....on your people’s communication and language skills, especially when we hear that primary school children may be at rick of becoming addicted to the habit. So widespread has texting become, however, that even pigeons have started doing it. (12)........ , in this case, it’s difficult to view the results as anything but positive.
Twenty of the birds are about to take to the skies with the task of measuring air pollution, each (13)................with sensor equipment and a mobile phone. The readings made by the sensors will be automatically converted into text messages and beamed to the Internet – (14)...............they will appear on a dedicated ‘pigeon blog’. The birds will also each have a GPS receiver and a camera to capture aerial photos, and researchers are building a tiny ‘pigeon kit’ containing all these gadgets. Each bird will carry these in a miniature backpack, (15)............ , that is, from the camera, which will hang around its neck.
 The data the pigeons text will be displayed in the form of an interactive map, which will provide local residents with up-to-the-minute information on thir local air quality.
(12)....................

Lakeview Railway Onboard Bicycle Policy

Would you like to use your bicycle to explore the Lakeview Corridor Scenic Area? Our trains have the ---131--- you need to safety transport your bike. When booking your ticket, just remember that reservations ---132--- for both you and your bicycle. Reserve your bicycle spot-----133---. There are a limited number of storage racks on each train. You are responsible for stowing your bike securely.
---134---. Lakeview Railway does not take responsibility for bicycles lost or damaged aboard our trains.

132............

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:
Life expectancy is the period of time that a person can expect to live. Life expectancy varies greatly between genders and cultures. It used to be that women had a lower life expectancy than men (1 in every 4 women died in childbirth), but now they live an average of four to five years longer than men. Life expectancy has been increasing rapidly over the last centuries. With the advent of such modern miracles as sewers, medicine and a greater understanding of how diseases are spread, our life expectancy has increased by 25-30 years.
In developing countries like Swaziland, where there is a high HIV/ AIDS rate, life expectancy is as low as 32.6 years. In developed countries like Australia, life expectancy rates are as high as 81 years. There are an increasing number of factors which can cancel out the disadvantages you have. The one that we are looking at now is how your career can affect your life expectancy. Choosing the wrong career can result in a shorter life!
If you want your career to positively influence your life expectancy, you have to be made of money. That's right. Rich people in wealthy areas of England and France live 10 years longer than the people in poorer areas. Having a successful career has its drawbacks, too if the result of hard work is stress.
Stress can lead to a number of psychological disorders such as depression, anxiety, fatigue, tension and aggression. These conditions may result in a lack of concentration and an increase in serious injuries at work. They can also lead to high blood pressure and heart attacks which seriously affect life expectancy.
If you are worried that your job might decrease your life expectancy, you probably need to avoid careers on "dangerous jobs" list such as timber cutters, pilots, construction workers, roofer, truck drivers.
So if you don't want to kick the bucket at an early age, choose a career in something other than timber cutting, but above all, remember to relax.

The word "They" in bold in paragraph 1 refers to     .

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:
Although management principles have been implemented since ancient times, most management scholars trace the beginning of modern management thought back to the early 19005, beginning with the pioneering work of Frederick Taylor (1856-1915) Taylor was the first person to study work scientifically. He is most famous for introducing techniques of time and motion study, differential piece rate systems, and for systemtically specializing the work of operating employees and managers. Along with other pioneers such as Frank and Lillian Gilbreth, Taylor set the stage, labeling his philosophy and methods “scientific management’. At that time, his philosophy, which was concerned with productivity, but which was often misinterpreted as promoting worker interests at the expense of management, was in marked contrast to the prevailing industrial norms of worker exploitation.
The time and motion study concepts were popularized by Frank and Lillian Gilbreth. The Gilbreths had 12 children. By analyzing his children’s dishwashing and bed making chores, this pioneer efficiency expert, Frank Gilbreth, hit on principles whereby workers could eliminate waste motion. He was memorialized by two of his children in their 1949 book called “Cheaper by the Dozen”.
The Gilbreth methods included using stop watches to time worker movements and special tools (cameras and special clocks) to monitor and study worker performance, and also involved
identification of “therbligs” (Gilbreth spelled backwards) - basic motions used in production jobs. Many of these motions and accompanying times have been used to determine how long it should take a skilled worker to perform a given job. In this way an industrial engineer can get a handle on the approximate time it should take to produce a product or provide a service. However, use of work analysis in this way is unlikely to lead to useful results unless all five work dimensions are considered. physical, psychological, social, cultural, and power.

Where in the passage does the author comment that the principles of scientific management were often misunderstood?

Choose the best answer:
Many factories dump waste into the river ___________ it is polluted.

Thank you for considering Partyon for your upcoming event. We welcome the opportunity to inform you about the areas we have available.---135---. Our patio, for instance, can hold up to 15 people. This space is ---136--- for small get-togethers. Our lounge area can fit up to 40 people. It is best suited for informal---137---. Then
there’s our grand dining room, intended for more formal parties. It offers accommodations for up to 60 guests. Moreover, we can--138-design either a lunch or dinner menu for you according to your specifications.

137.......................

 Choose the option  A, B, C or D that best fits the blank space in the following passage:

"At last it is here: tomorrow is the exam day. There is no more homework to do, you have done lots of (1)…..  and you have had plenty of useful practice with past papers. You have finished the (2)…. . So what should you do now? Probably the least advisable course of (3)…. would be to carry on studying late into the night, trying (4)….. to learn things you should have learned long ago and (5)…. in the morning with an awful headache.
 A far better idea is to practise, (6)….. a singer or a musician does, what you already knew. In order not to feel (7)…. the next day, go to bed early and get up at your usual (8)….. . You may be a little bit (8)….. but that is probably just a (10)…… of your determination to do will in the exam."

6. A far better idea is to practise, (6)….. a singer or a musician does, what you already knew.

Congratulations on your recent ---139--- in Tuchman's Autopay system. Thank you for signing up for this convenient billing system. Your automatic payments will begin with the next billing cycle on 1 March. ---140---. Your statements will come to you electronically and your payment will be deducted from your designated bank account. You may ---141--- the account from which the funds are withdrawn. Simply log in to the My Account section on our Web site https://www.tuchmans.ky, select Autopay, and follow the instructions to enter the alternate account information. Please contact customer service if you have ---142--- using Tuchman's Autopay.

141...................

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks.
                   The texting pigeons
Not everybody recognizes the benefits of new developments in communnicatons technology. Indeed, some people fear that text messaging may actually be having a negative (11).....on your people’s communication and language skills, especially when we hear that primary school children may be at rick of becoming addicted to the habit. So widespread has texting become, however, that even pigeons have started doing it. (12)........ , in this case, it’s difficult to view the results as anything but positive.
Twenty of the birds are about to take to the skies with the task of measuring air pollution, each (13)................with sensor equipment and a mobile phone. The readings made by the sensors will be automatically converted into text messages and beamed to the Internet – (14)...............they will appear on a dedicated ‘pigeon blog’. The birds will also each have a GPS receiver and a camera to capture aerial photos, and researchers are building a tiny ‘pigeon kit’ containing all these gadgets. Each bird will carry these in a miniature backpack, (15)............ , that is, from the camera, which will hang around its neck.
 The data the pigeons text will be displayed in the form of an interactive map, which will provide local residents with up-to-the-minute information on thir local air quality.

(14)....................

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions.
When John Mills was going to fly in an airplane for the first time, he was frightened. He did not like the idea of being thousands of feet up in the air. "I also didn't like the fact that I wouldn't  be in control," says John.
"I'm a terrible passenger in the car. When somebody else is driving, I tell them what to so. It drives everybody crazy."
However John couldn't avoid flying any longer. It was the only way he could visit his grandchildren in Canada.
"I had made up my mind that I was going to do it, I couldn't let my son, his wife and their three children travel all the way here to visit me. It would be so expensive for them and I know Tom's business isn't doing so well at the moment - it would also be tiring for the children - it's a nine-hour flight!" he says.
To get ready for the flight John did lots of reading about airplanes. When he booked his seat, he was told that he would be flying on a Boeing 747, which is better known as a jumbo jet. "I  needed to know as much as possible before getting in that plane. I suppose it was a way of making myself feel better. The Boeing 747 is the largest passenger aircraft in the world at the moment.
The first one flew on February 9th 1969 in the USA. It can carry up to 524 passengers and 3.400 pieces of luggage. The fuel for airplanes is kept in the wings and the 747's wings are so big that they can carry enough fuel for an average car to be able to travel 16,000 kilometers a year for 70 years. Isn't that unbelievable? Even though I had discovered all this very interesting information about the jumbo, when I saw it for the first time, just before I was going to travel to Canada, I still couldn't believe that something so enormous was going to get up in the air and fly. I was even more impressed when I saw how big it was inside with hundreds of people!"
The biggest surprise of all for John was the flight itself. "The take-off itself was much smoother than I expected although I was still quite scared until we were in the air. In the end, I managed to relax, enjoy the food and watch one of the movies and the view from the window was spectacular. I even managed to sleep for a while!
"Of course," continues John, "the best reward of all was when I arrived in Canada and saw my son and his family, particularly my beautiful grandchildren. Suddenly, I felt so silly about all the years when I couldn't even think of getting on a plane. I had let my fear of living stop me from seeing the people I love most in the world. I can visit my son and family as often as I like now!" 

Why did John Mills fly in an airplane?

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:
Although social changes in the United States were being wrought throughout most of the nineteenth–century, public awareness of the changes increased to new levels in the 1890's. The acute, growing public awareness of the social changes that had been taking place for some time was tied to tremendous growth in popular journalism in the late nineteenth century, including growth in quantity and circulation of both magazines and newspapers. These developments, in addition to the continued growth of cities, were significant factors in the transformation of society from one characterized by relatively isolated self–contained communities into an urban, industrial nation. The decade of the 1870's, for example, was a period in which the sheer number of newspapers doubled, and by 1880 the New York Graphic had published the first photographic reproduction in a newspaper, portending a dramatic rise in newspaper readership. Between 1882 and 1886 alone, the price of daily newspapers dropped from four cents a copy to one cent, made possible in part by a great increase in demand. Furthermore, the introduction in 1890 of the first successful linotype machine promised even further growth. In 1872 only two daily newspapers could claim a circulation of over 100,000, but by 1892 seven more newspapers exceeded that figure. A world beyond the immediate community was rapidly becoming visible.
But it was not newspapers alone that were bringing the new awareness to people in the United States in the late nineteenth century. Magazines as they are known today began publication around 1882, and, in fact, the circulation of weekly magazines exceeded that of newspapers in the period which followed. By 1892, for example, the circulation of the Ladies' Home Journal had reached an astounding 700,000. An increase in book readership also played a significant part in this general trend. For example, Edward Bellamy's utopian novel, Looking Backward, sold over a million copies in1888, giving rise to the growth of organizations dedicated to the realization of Bellamy's vision of the future. The printed word, unquestionably, was intruding on the insulation that had characterized United States society in an earlier period.

According to the passage, the expansion of popular journalism was linked to     .

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:
The elements other than hydrogen and helium exist in such small quantities that it is accurate to say that the universe is somewhat more than 25 percent helium by weight and somewhat less than 75 percent hydrogen.
Astronomers have measured the abundance of helium throughout our galaxy and in other galaxies as well. Helium has been found in old stars, in relatively young ones, in interstellar gas, and in the distant objects known as quasars. Helium nuclei have also been found to be constituents of cosmic rays that fall on the earth (cosmic rays are not really a form of radiation; they consist of rapidly moving particles of numerous different kinds). It doesn’t seem to make very much difference where the helium is found. Its relative abundance never seems to vary much. In some places, there may be slightly more of it; in others, slightly less, but the ratio of helium to hydrogen nuclei always remains about the same.
Helium is created in stars. In fact, nuclear reactions that convert hydrogen to helium are responsible for most of the energy that stars produce. However, the amount of helium that could have been produced in this manner can be calculated, and it turns out to be no more than a few percent. The universe has not existed long enough for this figure to be significant greater. Consequently, if the universe is somewhat more than 25 percent helium now, then it must have been about 25 percent helium at a time near the beginning.
However, when the universe was less than one minute old, no helium could have existed. Calculations indicate that before this time temperature were too high and particles of matter were moving around much too rapidly. It was only after the one-minute point that helium could exist. By this time, the universe had cooled so sufficiently that neutrons and protons could stick together. But the nuclear reactions that led to the formations of helium went on for only relatively short time. By the time the universe was a few minutes old, helium production had effectively ceased.

The word "vary" is closest in meaning to

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions:
Cities develop as a result of functions that they can perform. Some functions result directly from the ingenuity of the citizenry, but most functions result from the needs of the local area and of the surrounding hinterland (the region that supplies goods to the city and to which the city furnishes services and other goods). Geographers often make a distinction between the situation and the site of a city. Situation refers to the general position in relation to the surrounding region, whereas site involves physical characteristics of the specific location. Situation is normally much more important to the continuing prosperity of a city. If a city is well situated in regard to its hinterland, its development is much more likely to continue. Chicago, for example, possesses an almost unparalleled situation: it is located at the southern end of a huge lake that forces east-west transportation lines to be compressed into its vicinity, and at a meeting of significant land and water transport routes. It also overlooks what is one of the world’s finest large farming regions. These factors ensured that Chicago would become a great city regardless of the disadvantageous characteristics of the available site, such as being prone to flooding during thunderstorm activity.
Similarly, it can be argued that much of New York City’s importance stems from its early and continuing advantage of situation. Philadelphia and Boston both originated at about the same time as New York and shared New York’s location at the western end of one of the world’s most important oceanic trade routes, but only New York possesses an easy-access functional connection (the Hudson-Mohawk lowland) to the vast Midwestern hinterland. This account does not alone explain New York’s primacy, but it does include several important factors. Among the many aspects of situation that help to explain why some cities grow and others do not, original location on a navigable waterway seems particularly applicable. Of course, such characteristic as slope drainage, power resources, river crossings, coastal shapes, and other physical characteristics help to dertermine city location, but such factors are normally more significant in early stages of city development than later.

The word “ingenuity” in paragraph 1 is closest in meaning to     .

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks.
Throughout history, women have had responsiblity for healing the sick. However, it is only in ccomparative recent times that they have been allowed to train as doctors at medical schools in Britain. Yet in that short time, they have (61)....... an enormous contribution to modern medicine.
The first female doctors were nuns (62)........._ gave advice about diseases and (63)......... and prepared medicnes. In ancient Rome, women healers were considered skillful and respected. In Britain, for centuries, male doctors were suspicious of women who pratised medicine (64) ..........and in 1512 a law was passed making it illegal for them to do so. Women coulnd’t study medicine at universities (65).......... the 19th century and they only began to gain equality with male doctors in the 20th century.
(61)...........................

Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions:
Environmental pollution is one of the impacts of human activities on the Earth. Pollution occurs when pollutants contaminate the natural surroundings; which brings about changes that affect our normal lifestyles adversely. Pollution disturbs our ecosystem and the balance in the environment. Pollution occurs in different forms; air, water, soil, radioactive, noise, heat/ thermal and light Let us discuss the causes and effects of air pollution on mankind and the environment as a whole.
Air pollution is the most prominent and dangerous form of pollution. It occurs due to many reasons. Excessive burning of fuel which is a necessity of our daily lives for cooking, driving and other industrial activities; releases a huge amount of chemical substances in the air every day; these pollute the air. Smoke from chimneys, factories, vehicles or burning of wood basically occurs due to coal burning; this releases sulphur dioxide into the air making it toxic.
The effects of air pollution are evident too. The increase in the amount of CO2 in the atmosphere leads to smog which can restrict sunlight from reaching the earth. Thus, preventing plants in the process of photosynthesis. Gases like sulfur dioxide (SO2) and nitrogen oxide (NO) can cause acid rain.
The decrease in quality of air leads to several respiratory problems including asthma or lung cancer. Chest pain, congestion, throat inflammation, cardiovascular disease, respiratory disease are some of diseases that can be caused by air pollution.
The emission of greenhouse gases particularly CO2 is leading to global warming. Every other day new industries are being set up, new vehicles come on roads and trees are cut to make way for new homes. All of them, in direct or indirect way lead to increase in CO2 in the environment. The increase in CO2 leads to melting of polar ice caps which increases the sea level and pose danger for the people living near coastal areas.
Ozone layer is the thin shield high up in the sky that stops ultra violet rays from reaching the  earth. As a result of human activities, chemicals, such as chlorofluorocarbons (CFCs), were released into the atmosphere which contributed to the depletion of ozone layer.

What does the passage mainly discuss?