Which is NOT the meaning of the word“independent”（）
A. Not relying on
B. autonomous
C. self-directed
D. self-controlled
The common types of reading assignment in the university include______（）
A. required reading
B. extracurricular reading
C. recommended reading
D. proofreading
The floor attendant steps forward（）the guests
A. welcoming
B. welcome
C. to welcome
D. to welcoming
氟利昂制冷剂是否对臭氧层有破坏（）
A. 否
B. 是
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