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单选题
Even though relatively _____, the diesel engine is highly efficient and needs little servicing.
A
extremely
B
gracefully
C
costly
D
awfully
参考答案
参考解析
解析：
句意：虽然价格很昂贵，但是这种柴油发动机的效能非常高并且很少需要维修。costly高价的，昂贵的。extremely非常地；极端地。gracefully温文地。awfully非常，十分。
句意：虽然价格很昂贵，但是这种柴油发动机的效能非常高并且很少需要维修。costly高价的，昂贵的。extremely非常地；极端地。gracefully温文地。awfully非常，十分。
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