18. What is the function of air conditioning? A) It controls the indoor environment.
B) It changes climatic condition.
C) It sometimes cleans the air.
D) It only cools the indoor air.
19. Why is air-conditioning beneficial for office workers? A) They enjoy fresh air.
B) They feel active and not so tired.
C) They make more mistakes.
D) They are sleepy and exhausted.
20. The word EMPLOYEE in the text means... A) the owner of the company
B) a person who gives lectures
C) a person who works for somebody
D) a person that employs other people
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