If the gas blows back you must turn off the supply, as it is dangerous.

如果煤气管漏气，你必须关闭送气管，否则很危险。

youdao

If the gas blows back you must turn off the supply, as it is dangerous.

如果煤气管漏气，你必须关闭送气管，否则很危险。

youdao