她从那次考试失败中学到了一个重要的教训，即没有什么是一成不变的。

She learned an important lesson from failing that exam, ___namely that nothing is ever certain.

这个网络被我们城市四种最常用的交通工具使用，即公共汽车、汽车、自行车和摩托车，并且一直受到坑洼等问题的困扰。

This network is used by the four most used means of transport in our city, ___namely bus, car, bicycle and motorcycle, and has been plagued by problems such as potholes.

有三个关键因素需要考虑，即预算、时间线和资源。

There are three key factors to consider, ___namely budget, timeline, and resources.