The bus and rail systems could be on the hook for billions of dollars in payments because exotic deals they entered into with investors — which have since been declared unlawful tax shelters — have gone sour.
这个报道里面还有两个表达需要先解释一下,on the hook表示caught in a difficult situation,即“陷入困境(或者圈套)”,结尾的have gone sour的原形为go sour,表示“变质,变糟”等意思,在这里则强调实际的交易结果与他们之前的计划有出入,他们的期望被打破。
Shelter最常见的意思是“庇护、避难所”,例如:an air-raid/bomb shelter就是指“防空洞”。如果想表达“为某人提供庇护”,可以说give/provide shelter to someone。如:Provision of shelter was their main concern for the disaster victims.(为灾民提供避难处是他们最关心的事)。