附录A中大量出现plumbing一词，如writing plumbing,
The real solution is not just off-the-shelf plumbing, but rather standard off-the-shelf plumbing. If the plumbing is standard, the boundary problem goes away, and applications can utilize ready-made plumbing.
谢谢！
水管装置; 水暖工的工作; 管道工程;