为什么moonlight前面加the

表示特指月光，例如：

1、The moonlight poured in through the windows.月光透过窗户泻入室内。

2、The moonlight danced on the ripples of the lake.湖面泛着月光。

3、Would that we could live a long life| and together share the moonlight a thousand miles away!但愿人长久，千里共婵娟。（苏轼《水调歌头·中秋》）