Every person leaves a footprint. That’s what I learnt when I started to work as a private investigator 调查员 10 years ago. People pay restaurant bills with their bank card, check into hotels or travel around. In every case, they leave a trace. And because of this, I’m able to track them down even when they don’t want to be found. The first thing I do when I want to find out where someone is staying is to go to the neighbourhood where he used to live. It’s human nature to tell stories — which is why neighbours will tell me all they know when I ring at their houses. Sometimes, someone even talks about his friend’s dishonesty. Then I produce a pattern of my subject’s life: if he likes to have a holiday in Spain or in Italy, if he prefers two- or three-star hotels and where he might hide his assets( 资产 ) When I’ve got this life pattern, I start my research. Nine times out of 10, I find the people I’m looking for. I once investigated a lorry supplier who owed 欠债 £500,000 to a subcontractor( 分包商 ) The subcontractor wanted to find out if it was worth bringing charges 指控 against the supplier. I found out the supplier had moved assets 资产 to his son, who founded a new company offering the same product. It was all done within the law. There was no money to be got from that operation. However, I asked the son if I could speak to his father and he told me that his parent was On a long holiday in Spain and wouldn’t be back for a while. It didn’t take me long to find out that the father wasn’t in Spain . I went back to the son and this time he told me that his father might in Bulgaria , and I found him doing winter sports in a beautiful mountain area. He was living in a big house on a large piece of land he had bought for €400,000. This was exactly the kind of asset my customer was looking for. We learn from the text that a private investigator is one who ___________.