It can track supply chains or it can track anything in a city, say a smart city.

它可以跟踪供应链，也可以跟踪城市中的任何事物，比如说一个智能城市。

Many were marched hundreds of kilometres to the tracks chained at the neck, as slaves had been a century before.

许多人像一个世纪前的奴隶一样，脖子上被铁链锁住，被押送到几百公里外的铁轨上。