时节不寒冷，就不会知道松柏挺拔且郁郁葱葱的；事情不危难，就不会知道君子每日都在持守信念。

A person may cause evil to others not only by his actions but by his inaction， and in either case， he is justly accountable to them for the injury.

如果你不倾听客户的声音，你就已经落后了。

The power of abstraction is that it allows us to reason about systems at a higher level, without getting bogged down in the details.

最大的危险是不去冒险。