The adjective 亮 (liàng) means "bright" or "light," describing something that emits or reflects light. It can also be used as a noun meaning "light" or "brightness." For example, 一道亮光 means "a beam of bright light."
今天的月亮特别亮,我们出去散步吧。
Jīntiān de yuèliang tèbié liàng, wǒmen chūqù sànbù ba.
The moon is especially bright tonight; let's go for a walk.
你房间的灯太亮了,我睡不着。
Nǐ fángjiān de dēng tài liàng le, wǒ shuì bù zháo.
The light in your room is too bright; I can't fall asleep.
她的眼睛又大又亮,非常好看。
Tā de yǎnjing yòu dà yòu liàng, fēicháng hǎokàn.
Her eyes are big and bright, very beautiful.