translation.en: The cities that are going to be built — and there are many, and many big ones — we have to think of how to design them in a compact way so we can save travel time and we can save energy.
translation.zh: 有很多很多大城市将在未来建成， 我们必须考虑如何以更紧凑的方式来规划城市， 这样我们就能节省花在路上的时间，并节约能源。