She had a moon-like expression, as if her thoughts were drifting in a distant place.

moon-like 是由 moon（月亮）和 like（像...的）组成的复合形容词，中间用连字符连接。 moon 指"月亮"，这里取其象征意义，常用来形容"朦胧""梦幻""遥远"等特质。 like 作为后缀时表示"像...的""具有...特征的"。 moon-like 整体形容一种像月亮般朦胧梦幻、若有所思的表情或神态。