Compared with 2 million tons last year, our coal output has increased
three times; that is to say, our coal output has increased 8 million tons
this year.
A. to; to
B. to; by
C. by; by
D. by; to
网友回答
A. to; to
B. to; by
C. by; by
(答案→)D. by; to
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