Plumb 词形变化 Plumbs 复数 Plumbs 释义与例句 name 1. A surname. 相关短语 plumb bob [机] 铅锤 plumb line 铅垂线 plumb bobs plumb lines plumb crazy plumb rule n. 锤规，垂直准测规 plumb rules out of plumb [化] 不垂直