This gives them their color. However,when light travels from air to snow, some light is sent back,or reflected.

VOA: special.2010.01.05

Also sunglasses, definitely color sunglasses are definitely coming back, so.

还有太阳镜，有色太阳镜无疑又流行起来了。

推荐购物街 - SpeakingMax英语口语达人

Dollars are called greenbacks because that is the color of the back side of the paper money.

VOA: special.2009.11.15