Make sure you 've got the ac on high and practice with the klieg lights .

1.调高空调温度，练习适应聚光灯。

Seats in ac second class are firmly padded but comfortable .

空调二等座的坐垫比较硬，但是很舒服。

That is because the shifting current of ac runs to earth more easily than dc does .

那是因为频繁切换的交流电比直流电更容易传入地下。

Completed ac / dc cabinets are ready to become pinball machines .

已完成的交流/直流机柜准备成为弹球机。

But it was ac that truly signified the onset of man-made weather by both cooling air and controlling humidity .

但是只有空调第一次真正实现了既能降温又能控制湿度的人造天气。