They stopped adding smell into the ventilation system of the subway train or of the car of the train months before.

这种在地铁通风系统、或者只是在某一节车厢的通风系统内添加臭味的行为几个月前才停止。

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Via the study of existing ventilation system of the kitchen in the air-conditioning dining car, a new ventilation system was designed.

通过对现有空调餐车厨房通风系统的研究，设计了一种新的通风系统。

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She believed the solar-paneled roof would power the entire car, not just the ventilation system, as is actually the case.

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