There it will be turned into a U-shape, with its ends fastened in place using metal lines, and set adrift.

在目的地，该设备将变成U型，并利用铁圈将它的末端固定任其随波逐流。

The flagmen had very important jobs because of course you need to make sure the train is on the right track, the right set of metal lines, especially when they're coming in and out of a railroad station.

旗手的工作非常重要， 因为你当然需要确保火车在正确的轨道上， 正确的金属线组，尤其是当他们进出火车站时。