translation.en: I think it's one thing to say there's 140,000 planes being monitored by the federal government at any one time, and it's another thing to see that system as it ebbs and flows.
translation.zh: 我想大约有14万架飞机 随时被联邦政府监控， 但如果去观察这个系统的起伏，又是另外一回事。