VII- 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 from 53 to 62.
A useful definition of an air pollutant is a compound added directly or indirectly by humans to the atmosphere in such quantities as to affect humans, animals, vegetation, or materials adversely. Air pollution requires a very flexible definition that permits continuous change. When the first air pollution laws were established in England in the fourteenth century, air pollutants were limited to compounds that could be seen or smelled – a far cry from the extensive list of harmful substances known today. As technology has developed and knowledge of the health aspects of various chemicals has increased, the list of air pollutants has lengthened. In the future, even water vapor might be considered an air pollutant under certain conditions.
Many of the more important are pollutants, such as sulfur dioxides, carbon monoxide, and nitrogen oxides, are found in nature. As the Earth developed, the concentration of these pollutants was altered by various chemical reactions; they became components in biogeochemical cycles. These serve as an air purification scheme by allowing the compounds to move from the air to the water or soil. On a global basis, nature is output of these compounds dwarfs resulting from human activities. However, human production usually occurs in a localized area, such as a city.
In this localized region, human output may be dominant and may temporarily overload the natural purification scheme of the cycles. The result is an increased concentration of noxious chemicals in the air. The concentrations at which the adverse effects appear will be greater than the concentrations that the pollutants would have in the absence of human activities. The actual concentrations need not be large for a substance to be a pollutant; in fact the numerical value tells us little until we know how much of an increase this represents over the concentration that would occur naturally in the area. For example, sulfur dioxide has detectable health effects at 0.08 parts per million (ppm), which is about 400 times its natural level. Carbon monoxide, however, has a natural level of 0.1 ppm and is not usually a pollutant until its level reaches about 15 ppm.
What does the passage mainly discuss?
A.The economic impact of air pollution
B.What constitutes and air pollutants.
C.How much harm air pollutants can cause.
D.The effects of compounds added to the atmosphere.

Choose the best answer to fill in each blank:
Flowers (I)______ in summer and leaves gathered in autumn can be pressed and used to make beautiful designs, while larger flowers and sprays of leaves can be (II)_______ in an (III)_______ natural state by drying them, which is best done in the open air. (IV)________ of dried flowers make really beautiful winter decorations and will sometimes last for year (V)_______ end. 
(V)
A.for
B.at
C.in
D.on

Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions.
Julie had a training course in alternative medicine. She was able to help the man out of danger.
A.Much as Julie had a training course in alternative medicine, she was able to help the man out of danger.
B.Having trained in alternative medicine, Julie was able to help the man out of danger.
C.But for a training course in alternative medicine, Julie could have helped the man out of danger.
D.Despite training in alternative medicine, Julie was able to help the man out of danger.

Choose the best answer to complete the following questions
There’s been an increase................ all kinds of pollution in the past hundred years.
A.on
B.at
C.by
D.in

Multiple choice
Is she a friend of ___ ?
A.yours 
B.you  
C.your     
D.you’re

Sally has worked here_______ six months.
A.for
B.by
C.since
D.from

III. Choose the best answer A, B, C or D for each sentence.
Football has more                      than any other kinds of sports.
A.attract
B.attractive
C.attraction
D.attractively

I ran a marathon last week but I wasn’t fit enough. I ________ after 15 kilometers. 
           
A.stopped out
B.kept on         
C.dropped out      
D.set away

Let’s go for a walk, _________we?
A.will     
B.shall    
C.do       
D.must

Mark the letter A, B, C or D on your answer sheet to indicate the sentence that is closest in meaning to each of the following questions.
It was wrong of you to criticize her in front of her colleagues.
A.You are wrong about criticizing her in front of her colleagues.
B.You shouldn’t have criticized her in front of her colleagues.
C.You didn’t need to criticize her in the presence of her colleagues.
D.You must be mistaken about criticizing her with her colleagues.