This article explains_________．
A. the digiculties of exercising
B. why exercising is good for your health
C. important information to know about exercising
D. why people have some wrong ideas about exercising
A.betweenB.formC.sortD.way
A. between
B. form
C. sort
D. way
How will the government know what the air quality is？
A. The factories will test the air every day．
B. Scientists will test it every day．
C. A report will be publised．
D. They will ask homeowners．
________fun and good exercise，Car racing is a very useful skill．
A. For
B. About
C. Besides
D. Beside
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