Bài tập ôn luyện môn Tiếng Anh Lớp 8 - Unit 7: Pollution

ĐỂ NHẬN TRỌN BỘ WORD PHỤC VỤ GIẢNG DẠY HÃY LH ZALO O937-351-107
UNIT 7: POLLUTION
A. PHONETICS
I. Mark the stress in the following.
aquatic 	chemical	atomic	economic
botanical	energetic 	traditional 	terrific
historical 	scientific 	medical 	athletic
classical 	dramatic 	practical 	characteristic
technical	poetic	national	biological
II. Write the words from the box in the correct part of the table, according to the stress pattern.
historic specific musical scenic electrical artistic logical tragic natural
horrific scientific political comic physical technological heroic magic
global original systematic arrival emotional economical central
critical grammatical academic mathematical
Oo
Ooo
oOo
oOoo
oOo
oOoo
B. VOCABULARY AND GRAMMAR
I. Match the different types of pollution to the pictures.
water pollution 	soil pollution 	air pollution 	noise pollution
light pollution 	visual pollution 	radioactive pollution 	thermal pollution
1.
2. 
3. 
4. 
5.
6. 
7. 
8. 
II. Complete the sentences with the words or phrases in part I.
1. The smoke from planes, cars and factories causes________. 
2. There are many causes of________ including nuclear explosions, nuclear accidents and nuclear waste.
3. ________ can cause hearing loss and tinnitus.
4. ________can be caused by unattractive views, such as power lines, billboards, Street banners, open storage of trash, ugly buildings, etc.
5. ________can lead to the death of aquatic plants and animals.
6. ________can happen when the temperature of a body of water increases;
7. There’s just so much ________from the ground that we simply can’t see most of the stars.
8. The ever-increasing use of Chemicals such as pesticides and fertilizers is one of the main factors causing________.
III. Complete the sentences with the words from the box.
aquatic 	radioactive 	contaminated 	poison	 pollutant
dumped 	sewage 	untreated 	dead 	effects
1. ________ or wastewater should be treated before it is discharged into the river or ocean.
2. More and more waste and________ are poured into the water, the soil and the air.
3. The________ material is stored in a special radiation-proof Container.
4. Oil spills can cause the death of________ animals such as fish.
5. ________sewage can spread disease and contaminate drinking water sources. 
6. Cholera is transmitted through________ water
7. The health________ of air pollution include heart disease, lung cancer, and asthma.
8. Carbon dioxide is a dangerous air________.
9. Over 150,000 tonnes of waste are________ annually along the coastline.
10. Up to 100.000 fish were found________ along the river last week.
IV. Underline the right option.
The planet’s water reserves are constantly polluted by waste from agriculture, industries, and (1) sewage / sewers / sewing. Since water is always circulating through
the environment, it transports the (2) pollution / polluted / pollutants it contains from one area to the next. A pesticide that is (3) sprayed / spread / crowded on a field, for example, seeps into the groundwater, finds its way to a stream, and finally (4) ends up / gives up / comes up in the ocean. These toxic substances harm (5) poisonous / aquatic / dead plants and animals, and also infect the food Chain, causing certain plant and animal species to become (6) extinct / extinction / extincted. They can also (7) effect / defect / affect humans who eat fish. Even though (8) dumping / collecting / clearing garbage in the ocean is strictly forbidden, many countries release their (9) treated / untreated / treatment sewer waste and dispose of their garbage into the water. In addition to this, more than 6 million tons of oil are accidentally (10) spilled / littered / floated into the ocean every year.
V. Match the two halves of the sentence.
1. Overfertilization contributes to soil pollution, 
2. Because there is so much light pollution from the ground,
3. Lake, river, ocean and ground water get contaminated
4. Carbon monoxide is a poisonous gas 
5. The soil is exposed and vulnerable to erosion
6. The polluted fog became so thick
7. Since air pollution is a threat to human health,
8. People living near the airport aren’t getting enough sleep
a. because of aircraft noise.
b. due to discharge of pollutants in the water bodies.
c. everybody should try their best to reduce it.
d. as a result of the removal of vegetation.
e. so you only need to apply fertilizer
once or twice per year.
f. people cannot see the stars in the night sky.
g. that people could only see a few meters in front of them. 
h. that can lead to health problems.
VI. Choose the best answer to complete the sentences.
1. The river water is severely polluted, mostly________ the dumping of raw sewage.
A. due to	B. lead to	C. because	D. so
2. Sudden changes in water temperature can ________ mass killings of fish, plants, or
amphibians.
A. come up	B. result in	C. dump into	D. thank to
3. Water pollution________ the death of all forms of life in the water bodies.
A. occurs	B. results of	C. creates	D. leads to
4. ________ plastic takes so long to break down, it pollutes the land and ocean.
A. Because	B. Due to	C. Even if	D. Although
5. Many flights were cancelled ________ the smoke from forest fires.
A. so	B. because	C. because of	D. result in
6. ________the garbage dump smells terrible, no one lives around there.
A. Because of 	B. As	C. As a result of 	D. Even though
7. ________the grain consumption is rising, forests will be cut to provide more room for planting crops.
A. since	B. Although	C. unless	D. Due to
8. Grace didn’t love nature, ________ she wasn’t happy when her group went camping in a jungle.
A. but	B. and	C. because	D. so
9. Thousands of fish were killed ________ a discharge of poisonous Chemicals from a nearby factory.
A. because	B. lead to	C. result in	D. as a result of
10. ________the fog, there were no take-oils from the airport yesterday.
A. Since	B. Because	C. Owing to	D. Thanks to
VII. Complete the sentences with the verbs in brackets. Use conditional sentences type 1. 1. If the air in a City________ (get) very polluted, it can make people’s eyes burn.
2. If we dump all sorts of Chemicals into rivers, we________ (not be) able to swim in them in the future.
3. Many wildlife habitats will be destroyed if people________ (keep) polluting the environment.
4. If we all use public transport more, we________ (help) reduce air pollution.
5. If we________ (not stop) over-fishing the oceans, many species________ (become) extinct.
6. If everyone________ (recycle) paper, metal and glass, we ________ (not produce) so much rubbish.
7. We________ (have) dirty seafood if we________ (dump) rubbish into the sea.
8. If global warming________ (continue), temperatures________ (rise) even higher.
9. If light pollution________ (keep) growing, you________ (not be) able to see even the Big Dipper at night.
10. We________ (threaten) our own existence if we________ (not cut down) the waste rapidly.
VIII. Complete the sentences with the verbs in brackets. Use conditional sentences type 2.
1. If people________ (not be) so careless, Earth wouldn’t be in danger.
2. The amount of waste ________ (decrease) if people started to buy reusable packages.
3. Many fish wouldn’t die if factories________ (not dump) so many Chemicals into rivers and oceans.
4. If people stopped using cars completely, there________ (be) much less pollution.
5. If people________ (buy) more recycled paper, there wouldn’t be so much waste.
6. If we________ (not bury) Chemical waste underground, we	________ (not pollute) fresh water supplies.
7. Pollution________ (not be) such an issue if governments and common people really ________ (care).
8. What	________ (happen) if the whole world________ (be) full of pollution?
9. If people________ (pay) a little more attention to the environment, the Earth________ (be) greener.
10. If people no longer________ (pollute) the atmosphere, the air________ (soon become) clean again.
IX. Write conditional sentences type 2, using the cues given.
1. What/ happen/ if/ water pollution/ stop?
______________________________________________________________________	
2. We/ be/ happy/ if/ air pollution/ the world/ be/ a/ better place?
______________________________________________________________________
3. If/ there/ be/ no more pollution/ the world/ be/ a better place?
______________________________________________________________________
4. If/I/ be/ you/I/ take/ these bottles/ the bottle bank.
______________________________________________________________________
5. If/ people/ not really care/ the environment/ they/ not try/ save it.
______________________________________________________________________
6. The river/ not be/ so polluted/ if/ factories/ not dump/ waste/ it.
______________________________________________________________________
7. We/ be/ less worried/ if/ oil spills/ not have/ such destructive effects.
______________________________________________________________________
8. If/ we/ destroy/ the ozone layer/ what/ save/ us/ the UV rays?
______________________________________________________________________
X. Complete the passage with the correct form of the verbs in brackets.
The problem of global warming would improve if we all (1) ________ (do) something to reduce it! For example, if we all (2) ________ (turn off) our mobile phone chargers at night, we’d save a lot of energy. And we ________ (save) a lot of water if we all (4) ________ (turn off) the tap when cleaning our teeth. If we (5) ________ (recycle) more, less rubbish (6) ________ (go) to landfill sites. And if we (7) ________ (cycle) more, our parents (8) ________ (not need) to use their cars so often. Let’s make a difference!
XI. Complete the sentences with the correct form of the verbs in brackets.
1. If we________ (not recycle) paper now, we’ll need to cut down more trees in the future.
2. If the local people________ (have) fresh water, they wouldn’t have to use polluted water.
3. What________ (happen) if radioactive material was not handled properly?
4. If we recycle more household waste, there________ (be) less damage to the environment.
5. If we________ (not understand) environmental problems, we would not be able to do anything about them.
6. If the polar ice-caps melted completely, Sea levels worldwide________ (rise) about 60 metres.
7. The amount of plastic in the ocean________ (increase) if we________ (not take) action now.
8. These fish________ (not die) if the factory ________ (not dump) its toxic waste into the river.
9. There ________ (not be) enough oxygen if we ________ (not protect) the rainforests.
10. If I ________ (be) the President, I ________ (ban) billboards in cities in order to reduce visual pollution.
XII. Use the correct form of the word given to complete each sentence.
1. It’s evidence that this ocean is clean and environmentally________. (pollute)
2. Diseases are primarily due to________ food and air. (contaminate)
3. While some Chemicals may be harmless others can cause________. (damage)
4. Life expectancy has gone down due to________ diseases caused by air pollution. (die)
5. In remote regions, the air is pure and the crops are free of ________ insecticides. (poison)
6. Some scientists warn that light________ damages people and animals. (pollute)
7. Many Chemicals have a________ effect on the environment. (damage)	
8. The dumping of________ I sewage into the sea is a source of ocean pollution. (treat)
9. A________ is a substance that makes something dirty, polluted, or poisonous. (contaminate)
10. Water pollution can lead to the________ of aquatic plants and animals. (die)
XIII. Underline the correct preposition in each of the following sentences.
1. Water pollution can be harmful at / to fish and animals that live along the river.
2. Using drinking water to water the garden is a waste from / of natural resources.
3. Ways must be found to prevent the poisonous gases on / from polluting the air.
4. Textile factories dump tonnes of toxic waste into / at the Citarum River.
5. She’s come up to / with amazing new ideas to help protect the environment.
6. Noise pollution can have harmful effects on / in human health.
7. The overuse of pesticides causes damage in / to the environment.
8. Too much of light pollution results in / of increase in the energy consumption.
9. The river has been polluted with / from toxic waste from local factories.
10. Children should be aware at / of the environmental issues we’re facing.
C. SPEAKING
I. Make questions for the underlined words.
1. ______________________________________________________________
Water pollution is the contamination of water bodies, such as lakes, rivers and oceans. 
2. ______________________________________________________________
The river water is heavily contaminated because of toxic waste dumping.
3. ______________________________________________________________
There are five major types of pollution.
4. ______________________________________________________________
If I were the President, I would ban cars from city centres.
5. ______________________________________________________________
Most of the plastic waste ends up in the oceans. 
6. ______________________________________________________________
Death or disfiguration are common effects of exposure to radioactive waste.
7. ______________________________________________________________
Ho Chi Minh City is more polluted than Panang.
8. ______________________________________________________________
In my neighbourhood, garbage is collected everyday.
9. ______________________________________________________________
Every individual is responsible for solving environmental issues.
10. ______________________________________________________________
Land pollution can be prevented by the proper disposing of the litter.
II. Complete the dialogue with the appropriate sentences (A- H).
A. Because I’m doing a class project on pollution in the city.
B. Too many billboards along the road, open storage of trash; networks of electric wires crisscrossing each other above the street, etc.
C. Visual pollution is what you would call anything unattractive or visualizing or damaging to the landscape.
D. It generates distraction, eye tatigues and other psychological problems.
E. Yeah, I know. Not only water pollution, but also for air, soil noise, light and visual pollution.
F. Yes, I took it yesterday.
G. Exactly! Garbage on riverside.
H. I think so too.
Bailey: Did you take that photo, Xuan?
Xuan: (1)___________________________________________________	
Bailey: Let me see. A photo of a river... but it looks like you want to capture the garbage.
Xuan: (2)___________________________________________________	
Bailey: Why garbage?
Xuan: (3)___________________________________________________	
Bailey: This picture is for water pollution, isn’t it? I think you need more.
Xuan: (4)___________________________________________________	
Bailey: Visual pollution? I’ve never heard about it before.
Xuan: (5)___________________________________________________
Bailey: Can you give me some examples?
Xuan: (6)___________________________________________________	
Bailey: So what are the effects of visual pollution?
Xuan: (7)___________________________________________________
Bailey: Oh, I see. There is too much visual pollution in the City, so I think it’s not difficult to take photos of different visual pollutants.
Xuan: (8)___________________________________________________
D. READING
I. Complete the passage with the words from the box.
honking 	loss 	commonly 	source referred 	rural 	 unheard 	even
A screaming child, TV blaring in the living room, a vacuum cleaner, loud music coming from a teen’s bedroom: a busy home can be a (1) ________ of constant noise. Once you step outside, there’s (2) ________ more noise pollution. On an average day, you may hear your neighbour’s lawn mower, (3) ________ cars, sirens, maybe even ear-shattering sounds of a construction or a work site-a saw, a drill, a jackhammer. Welcome to the modern - and very noisy - world. Unless you live in a very quiet (4) ________ area, you are no stranger to the phenomenon of environmental noise, (5) ________ called noise pollution. Noise pollution is often (6) ________ to as the “modern unseen plague” for good reason. It may be unseen but certainly not (7) ________! It disturbs us practically everywhere we go, day and night. And, besides leading to hearing (8) ________ it impacts our physical and mental health in more ways than one.
II. Read the passage, then do the tasks.
According to Greenpeace, more than 100,000 sea creatures and a million sea birds die every year after eating plastic or getting trapped in plastic rubbish. Sometimes, when baby turtles get trapped in plastic the shape of their Shell changes when they grow. Some sea creatures make their homes in plastic rubbish, such as the hermit crabs that live on polluted Pacific beaches.
Every year, the world produces more than 300 million tonnes of plastic! In a minute, people around the globe use more than a million plastic bags and they throw away more than a million plastic bottles. Where will all this plastic end up? About 10% of it will be recycled, and some will go to landfill, but a lot of it will end up polluting the oceans. Experts estimate that there are already 200 million tonnes of plastic in the world’s oceans, and this will increase by about 7 million tonnes every year.
Because plastic isn’t biodegradable it won’t decompose naturally, so all the plastic that we have now in the world will exist forever. That means we’ll need to clean up the oceans if we want to protect our sea creatures. Better still, if we don’t use so much plastic, it won’t end up in the ocean! Experts are warning that if we don’t take urgent action, there might be more plastic than fish in the sea by 2050.
A. Match the words to their definitions.
1. getting trapped
2. shell
3. end up
4. landfill
5. clean up
6. biodegradable
a. finish, arrive
b. make something free from pollutants
c. able to decay naturally by bacteria
d. being unable to escape from
e. the hard part on the back of a turtle
f. a place in the ground to put rubbish
B. Decide whether the following statements are true (T) or false (F).
1. Plastic rubbish kills a million birds every year.
2. The hermit crabs living on Pacific beaches die because of plastic pollution.
3. Around the world, people use more plastic bottles than bags.
4. Less than half of plastic bottles and bags end up getting recycled.
5. Plastic rubbish will disappear naturally over time.
6. It is predicted that there will be more plastic than fish in the oceans by 2050.
C. Answer the questions.
1. What never decomposes?
______________________________________________________________
2. How many tones of plastic are dumped in the oceans every year?
______________________________________________________________
3. Why do we need to clean up the oceans?
______________________________________________________________
4. What can we personally do to help resolve this problem?
______________________________________________________________
E. WRITING
I. Reorder the words to make full sentences.
1. of bodies/ directly/ Air pollution/ contaminate/ can/ of water and soil/ the surface. 
______________________________________________________________
2. trees/ so much/ don’t/ We/ if/ we/ waste/ will/ thousands of/ paper/ save.
______________________________________________________________
3. would/ bad/air pollution/ What/ got/ you/ really/ do/ if?
______________________________________________________________
4. as/ the death/ Polluted water/ animals/ of/ fish and crabs/ such/ aquatic/ causes.
______________________________________________________________
5. went/ more/ less/ to/ If/ we/ recycled/ rubbish/ landfill sites.
______________________________________________________________
6. the overuse/ has/ Agriculture/ on/ an/ land pollution/ impact/ of/ Chemicals/ due to.
______________________________________________________________
7. much/ cities/ lights/ use/ Too/ of/cause/ in/ may/ light pollution/ electric
______________________________________________________________
8. our time/ is/ one/ most/ of/ problems/ serious/ Water pollution/ the/ of/ environmental
______________________________________________________________
II. Complete the second sentence so that it has the same meaning to the first one.
1. I think you should use energy efficient light bulbs.
If I_________________________________________________________________
2. He produced a great idea for our environmental project.
He came_____________________________________________________________
3. Because she was absent from the meeting, she didn’t know the resolution.
Because of___________________________________________________________
4. I won’t take part in the volunteer program because I don’t have enough free time.
If I_________________________________________________________________
5. We need to reduce our plastic waste, otherwise we’ll threaten our own existence,
If we________________________________________________________________
6. Due to the hurricane last night, I was without electric power.
Since there___________________________________________________________
7. People dumped toxic waste Products into the rivers or landfill sites.
Toxic waste products___________________________________________________
8. Air pollution deaths will double by 2050 if nations don’t act.
Unless_______________________________________________________________
9. As the world’s temperatures rise, the Arctic keeps losing its ice.
Due to_______________________________________________________________
10. I live by the sea, so I’m really worried about global warming.
If I__________________________________________________________________
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TEST FOR UNIT 7
I. Choose the word whose underlined part is pronounced differently from the others.
1. A. disease	B. dead	C. treatment	D. sneeze
2. A. environment	B. billboard	C. visual 	D. litter
3. A. birth	B. thermal	C. earth	D. further
4. A. poisoned	B. died	C. dumped	D. caused
5. A. contaminant	B. waste	C. illustrate 	D. radiation
II. Choose the word whose main stress pattern is placed differently.
1. A. environment	B. temperature	C. botanical	D. contaminant
2. A. untreated	B. aquatic	C. pollution	D. electronic
3. A. pollute	B. poison	C. damage	D. illustrate 
4. A. presentation	B. radioactive	C. environmental	D. contamination
5. A. permanent	B. Chemical	C. dramatic	D. herbicide
III. Complete each sentence with an appropriate word. The first letter of each word is given.
1. The fish have died because the river water is heavily p________.
2. Health e________ from air pollution include lung cancer, and respiratory diseases.
3. Acid rain causes serious d________ to plants and trees.
4. If the air wasn’t dirty, Nick w________ sneeze so much.
5. The main gases that l________ to acid rain are sulfur dioxide and nitrogen dioxide.
6. There is a danger of serious contamination from radioactive w________.	
7. Hundreds of d________ fish were found floating in the river near the factory.
8. U________ sewage can spread disease and contaminate drinking water sources.
IV. Choose the best answer A, B, C or D to complete the sentence.
1. After the accident, many people were exposed________ radiation.
A. from	B. at	C. to	D. with
2. Light pollution has a wide range of negative effects________ I’m human health.
A. on	B. of	C. for	D. to
3. ________can cause high blood pressure, heart problems, sleep disturbances, and hearing problems.
A. Air pollution 	B. Light pollution 	C. Water pollution 	D. Noise pollution
4. The levels of carbon dioxide in the atmosphere have risen________ the burning of fossil fuels.
A. therefore	B. because	C. in spite of	D. due to
5. If rubbish is non-biodegradable, it________ forever.
A. exists	B. will exist	C. won’t exist	D. doesn’t exist
6. ________are Chemicals that are used to kill unwanted plants, such as weeds.
A. Fertilizers	B. Pesticides	C. Herbicides	D. Pollutants
7. There would be much less pollution________ people stopped using cars completely.
A. if	B. since	C. when	D. although
8. Emissions of pollutants into the air can________ changes to the climate.
A. get on	B. end up	C. go into	D. result in
9. ________can we help save our environment?
A. What	B. How	C. Why	D. How much
10. If we care about plastic waste________. 
A. why won’t we stop drinking bottled water? 	B. we would use reusable shopping bags
C. we will throw away plastic water bottles. 	D. why don’t we buy plastic bags?
V. Choose the underlined word or phrase, A, B, c or D that needs correcting.
1. What will happen if the Earth stopped moving?
 A B C D
2. One of the things all of us can do to protect and improve our environment is recycle.
 A B C D
3. Humans can even die if they will drink contaminated water.
 A B C D
4. Long-term exposure to loud noise results permanent hearing loss.
 A B C D
5. They believe that water pollution is the large cause of death and disease in the world.
 A B C D
6. Is the recycling process in itself damaging for the environment?
 A B C D
7. We won’t save the environment if we stop using so much energy.
 A B C D
8. One in six species is at risk of extinction because climate change.
 A B C D
9. The amount of waste decreased if people started to buy reusable packages.
 A B C D
10. Contaminated water can cause of many types of diarrheal diseases, including cholera.
 A B C D
VI. Write the correct tense or form of the verbs in brackets.
1. It would be better for the environment if more people________ (use) bikes rather than cars.
 2. If we use less energy, we________ (help) reduce greenhouse gas emissions.
3. Every year, million tons of plastic________ (dump) into the oceans.
4. A thick smog________ (settle) over New Delhi since winter________ (begin).
5. Noise pollution can________ (cause) by vehicle, aircraft, and industrial noise.
6. Human activities________ (destroy) nature at an unacceptable rate right now.
7. A decade ago, WHO________ (classify) air pollution as a link to lung cancer.
8. If the temperature________ (increase) by a few degrees during the next few years, we________ (run into) serious problems.
9. What________ (happen) if all the pollution in the world________ (disappear)?
10. At 8 o’clock last night, I________ (watch) “A Plastic Wave”, a documentary on plastic pollution.
11. We should avoid ________ (buy) frozen foods because their packaging is mostly plastic.
12. Air pollution can make people ________ (die).
VII. Supply the correct form of the words in brackets.
1. As an________ why do you oppose banning plastic bags? (environment)
2. The radiation leak has had a________ effect on the environment. (disaster)
3. The water supply is being tested for	________. (contaminate)
4. Heavy metals in________ water cut short millions of lives every year. (drink)
5. Scientists warn that plastic pollution in oceans will be one of the ________ threats. (big)
6. Pollution is the process of making parts of the living environment________. (dirt)
7. If thermal pollution continues for a long time, it can________ cause huge bacteria. (possible)
8. She became deaf after long-term________ to noise in the workplace. (expose)
9. Living near a busy road could cause high blood________. (press)
10. Wastewater________ a process used to remove contaminants from sewage. (treat)
VIII. Match the questions to the answers.
1. What is the main reason for thermal pollution?
2. What effect does thermal pollution have on aquatic animals?
3. How to minimize the water pollution due to Chemicals?
4. What diseases are usually caused by air pollution?
5. Which gas is mainly responsible for global warming? 
6. What are the effects of noise pollution?
7. Why are plastic bags a big environmental nuisance?
8. What are sources of radioactive pollution?
a. They are non-biodegradable and create an environmental harzard.
b. Nuclear wastes from nuclear power plants, mining and processing of nuclear material etc.
c. Carbon dioxide. It contributes about 55% to global warming.
d. It affects their growth and may kill off them.
e. Hot water released by power plants and industries.
f. Sleep disturbance, high blood pressure, emotional problems and annoyance.
g. Rickets, throat cancer, lung cancer and breathing problem.
h. Treat wastewater before discharging into a flowing body of water.
IX. Choose the word which best fits each gap.
Many human activities over the last 200 years have been responsible (1) ________ polluting the air and damaging people’s health. Automobile engines and power plants burn combustible (2) ________ like gasoline and coal and allow toxic gases and smoke to escape into the air. Some pollutants destroy the ozone layer, which is the thin blanket of gases that (3) ________ Earth from the Sun’s dangerous ultraviolet rays. Other pollutants contribute to (4) ________ warming by adding to the planet’s natural greenhouse effect. Still others create acid rain, a phenomenon that has disastrous (5) ________ on lake and forest habitats. Air pollution is not limited to industrial areas. Depending on the direction of the wind and its force, air pollutants may (6) ________ spread to other countries very far from the source of the pollution.
Big cities like Los Angeles and Mexico City are*often covered by smog, a fog that occurs (7) ________ air pollution. In 1952, the City of London, England, was enveloped by smog so thick that people on the streets had to feel their way around by (8) ________ the walls of buildings!
1. A. for	B. of	C. to	D. with
2. A.