English Test 20
Clean air provides us with a healthy supply of oxygen. When wastes are poured (1) ______ the atmosphere, the
air becomes contaminated and unpleasant to breathe. This is air pollution.
Water vapour and carbon dioxide occur in the air naturally. Examples of air pollution are dust storms, volcanic
eruptions, forest fires (2) ________ by lightning, pollen, and marsh gases.
A large (3) ______ of air pollution in cities comes from sources other than industry, mainly automobiles, home
heating, and garbage disposal
Vehicles also account (4) ______ air pollution in the cities. Automobiles exhaust and some industrial processes
contain carbon monocide, an odourless gas which cannot be seen or tasted. Nitric oxide is another tail – pipe
emission that is highly poisonous and may sometimes (5) _____ into the even more dangerous nitrogen dioxide.
Lead andsmoke are emitted in engine exhausts as tiny particles.
Smog - originally a combination of smoke and fog – also (6) ____ in the atmosphere when nitrogen oxides and
organic gases combine under the influence of sunlight. This is photochemical smog. It may not sound familiar,
but it is commonly found in most major cities (7)___ there are large concentrations of industry and automobiles.
Industrial smoke stacks throw out sulphur and nitrogen oxide.
Burning coal and oil releases other gases harmful (8) _____ humans. The most serious of these gases is sulphur
dioxide. In the atmosphere it can (9) _______ with water vapour and oxygen to turn into a sulphuric – acid mist.
Hydrogen fluoride is produced in the manufacture of phosphate fertilizers and some metals.
Burning garbage and paper wastes pollute the air with unpleasant odours. Dangerous chemicals can be released
(10) _______ burning plastics or hairspray containers.
New words
Contaminate Pollen Disposal Nitrogen dioxide ( NO2)
Vapour Exaust photochemical Oxygen ( O )
Emission ( Emit ) Account for Carbon monoxide ( CO) Sulphur ( S )
Release Stag Hydrogen fluoride ( HF ) Sulphur dioxide ( H2SO4 )
Marsh Organic Nitric oxide ( NO) Sulphuric acid ( HF )
Comprehension
1.Paragraph 1 gives you a way of understanding air pollution. What is it ? _______________________
2. What two gases occur naturally ? _______________________
3. What are some sources of air pollution in cities ? _______________________
4. How do vehicles pollute the air in cities ? _______________________

Conflicting Come into being Slash and thrust
Comprehension
A – Read the following sentences and then choose the Same or Different.
1.In England people can drive on the right in the passage and court at the Strand entrance to the Savoy Hotel.
2.The custom of driving on the left dates back to the days when English people went to and from on horseback.
3. In a guide book, an English author mentioned that the left–hand rule was put in force by Napoleon Bonaparte.
4.Men on horseback used to have a practice of running each other though with swords in their left hands.
Unit 7: Being a welcome guest.
When people in the US have company or when they are invited (1) ____ a formal or informal get – together
they usually make a point of trying to (2) ____ others feel compfortable and relaxed. On the whole, they tend to
be informal. Man shake hands, but usually (3) _____ when they are introduced. Male friends and business
associates who haven’t seen each other in a while may shake hands when they say hello. Women usually don’t
shake hands when being introduced (4) _each other. When a woman and a man are introduced, shaking hands is
up to the woman. Americans rarely shake hands to say goodbye, except on business occasion.
American women are used (5) ______ being independent. They are used to going places by themselves, earning
their own money, and often living alone. Sometimes they will ask men for help, but they usually don’t want to be
protected. Since the women’s movement started, it’s not always clear whether except men to open doors or help
them into their coats. American women may start conversation (6) ____ men or even ask them to dance.
There are a lot of Americans who don’t smoke or drink, and many who don’t want people to do those things in
their house. It’s always best to ask before you (7) ___ up a cigarette, if you are with people you don’t know very
well. Non – smokers have become more militant about smoking in public places. Many restaurants, for instance,
have established special sections (8) _______ smokers.
House guests may bring gifts when they come to visit, and they often offer to help in some ways. As a guest ,
you may want to ask your host or hostess if there’s anything you can do to help in the kitchen. In many (9)
______, the gesture is more important than actually helping. You may also want to take your friend out to dinner
(10) _____ the end of your stay, but it’s not expected for you to do so.
New words.
1. company 4. help sb into one’s coat
2. get – together 5. light up
3. make a point of doing 6. special section