keepv.保持；保留；继续；贮藏；经营；遵守；供给；照管；饲养；耽搁；保持食物不变质；健康状况如何；保守（秘密@）；记录；遵守；保护n.生计；保存；城堡主楼；监狱；围墙keep clear让路

1. Gas flowing through the pipes burns instantly but can be kept under control easily by opening or closing the pipes.
   通过管子的煤气会瞬间燃烧起来，但我们凭开、关管道很容易控制它。