3 sentences

1. 大约50秒后，红灯亮了。

   dà​yuē50 miǎo hòu, hóng​dēng liàng le.

   After about fifty seconds, the red light came on.

   Source: CCMatrix

2. 楼上的灯亮着。

   lóu​shàng de dēng liàng zhe.

   The light's on upstairs.

   Source: OpenSubtitles

3. 小绿灯亮着呢。

   xiǎo lǜ​dēng liàng zhe ne.

   The little green light's on.

   Source: OpenSubtitles