But there's lot of indoor air pollution, too, even if it's not as obvious.

但是，虽然并不明显，但是室内也存在大量的空气污染。

The World Health Organization warns that millions of people are dying every year from indoor air pollution.

世卫组织警告称每年有数百万人因室内空气污染而死亡。

Cooking and heating with such solid fuels on open fires or stoves without chimneys leads to indoor air pollution.

用此类固体燃料在明火或没有烟囱的开放炉灶上做饭、取暖会导致室内空气污染。