the ventilation window
通风窗
以上为机器翻译结果，长、整句建议使用 人工翻译 。
Smoke travels upwards, and if smokers are confined to the top level and adequate ventilation is in place (be it an open window or a small fan), then there can be no cause for concern to those non-smokers who sit downstairs.
BBC: TRAPPED BY INCONSIDERATE SMOKERS
应用推荐
模块上移
模块下移
不移动