translation.en: If you look at the x-axis of this graph, you'll see that what we commonly want to do -- which is keeping the outdoors out -- we accomplished that with mechanical ventilation.
translation.zh: 如果你观察图表的横轴 你会发现我们通常希望做的是-- 阻止室外空气进入-- 我们通过机械通风设备达到了这个目的