A man sat in the cab attached to the trailer vehicle. 一个人坐在拖车的驾驶室中。
Tubes are generally mounted on truck trailer chassis, railroad car beds, or placed at stationary locations when large amounts of helium are needed. 管道一般是安装在拖车底盘或有轨车底座上，或者当需要大量氦时放置在固定位置。
