28. Most air pollution is caused by the burning of ______ like coal, gas, and oil.

A. fuels

B. articles

C. goods

D. products

29. The rising _____ did a lot of _____ to the crops.

A. water; harm

B. water; harms

C. waters; harm

D. waters; harms

30. The beach is a _____ throw from our house.

A. stone

B. stones

C. stones’

D. stone’s

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