Translation of "sleepers" into Chinese

A high density polyethylene railway sleeper

采用高密度聚乙烯研制的铁路轨道枕木

I assume you're a sound sleeper, Dr. Brennan.

我 猜 你 一定 睡眠 很 好 Brennan 博士

The progress in railway reconstruction, however, is slow, owing to the lack of steel strands for the production of concrete sleepers

铁路重建工作迟迟不前,因为缺少生产水泥轨枕所需的钢绳。