0 flat, having width and length but not depth -- 二维的,平面的
1 A person or story that is two-dimensional is too simple, showing little deep, serious thought, or understanding -- (人或故事)无深度的,肤浅的,浅薄的
I didn't believe in any of the characters in the book - they were somehow two-dimensional. 我不相信书中的任何人物——他们被刻画得都有点肤浅。