translation.en: But there's a problem that I would call the "3S" menace: The scale, speed, and scarcity of means with which we will have to respond to this phenomenon has no precedence in history.
translation.zh: 但这里有一个问题， 我将它称之为“3S威胁“： 规模，速度和资源匮乏， 即在城市化过程中，我们面对的这三个威胁 是史无前例的。