重点讲解：
1. in operation
使用；运作；
eg. Until the rail links are in operation, passengers can only travel through the tunnel by coach.
在铁路连线开通之前，乘客只能乘坐长途客车穿越隧道。
eg. There are three ski lifts in operation.
有3台滑雪缆车在运行。
2. be interested in
感兴趣的；有兴趣的；关心的；
eg. He's told people that he's interested in going hunting.
他跟大家说，他对外出打猎开始感兴趣了。
eg. We're interested in the source of these fictitious rumours.
我们对这些子虚乌有的谣言从何而来很感兴趣。
3. when it comes to
谈到；涉及；
eg. Perspective taking is particularly useful when it comes to your boss.
面对上司的时候，换位思考尤其有效。
eg. When it comes to expressing himself he is no shrinking violet.
他在表达自己的想法时毫不羞怯。
