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刷刷题刷刷变学霸
举一反三
【单选题】To swim across the English Channel takes at least nine hours. It’s a hard work and it makes you short of breath. To fly over the Channel takes only twenty minutes, but it’s an expensive way to travel....
A.
not more expensive to be built than a bridge
B.
not more expensive to be built than a rail
C.
. cheaper to be built than a rail
D.
not cheaper to be built than a bridge