plumb基本解释
vt,[数]使垂直；探测，探索,同近
Psychologists try to plumb the deepest mysteries of the human psyche..心理学家试图探究人类心理最深层的奥秘。
使垂直；探测，探索中释v
plumb line,铅垂线（等于plumb rule）.短语
