问题
选择题
Most air pollution is caused by the burning of _____ like coal, gas and oil. [ ]
A. fuels
B. articles
C. goods
D. products
答案
答案：A
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Most air pollution is caused by the burning of _____ like coal, gas and oil. [ ]
A. fuels
B. articles
C. goods
D. products
答案：A
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