Or, if we know the equation of state from a model, ideal gas, van der Waal's gas, whatever, u now we can determine u.

或者如果我们知道模型的状态方程,比如理想气体，范德瓦尔斯气体，无论什么，我们就可以利用状态方程得到内能。

麻省理工公开课 - 热力学与动力学课程节选

But for the van der Waal's gas, now it's going to be different.

但是对于范德瓦尔斯气体，情况就不一样了。

麻省理工公开课 - 热力学与动力学课程节选

Now, Ludwig van Beethoven was in his fifties when he was working on his last symphony-- what would prove to be his last symphony-- his Ninth Symphony, and he'd been tinkering with this particular melody all the way back to probably 1803, so it's about twenty years or so.

路德维希·凡·贝多芬在五十多岁时,创作了他最后一首交响乐,后来成为他最后的交响曲,就是他的第九交响曲,他一直在锤炼这段旋律,也许要追溯到一八零三年,所以大概经历了二十个年头

耶鲁公开课 - 聆听音乐课程节选