around the clock字面意思围绕着钟表，可以想象一下，如果一个人一直围绕着钟表在转，这个人肯定是连休息的时间都没有了！所以around the clock被理解为全天候的，昼夜不断的，夜以继日地。

【例句】
People who do very important jobs sometimes have to work around the clock.
有重要工作的人，有时必须夜以继日地工作。

It's important to note that the increased flexibility didn't encourage them to work around the clock.
必须指出的是，增加工作灵活性，但并不鼓励员工全天候工作。