There is a sign at the train station, reading “Don’t jump off a train when it’s.”A. on mov

There is a sign at the train station, reading “Don’t jump off a train when it’s .”
A. on move
B. on a move
C. on the move
D. moving

A. on moveB. on a move(答案→)C. on the moveD. moving解析：可联系答.案.网客服索取。

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