这个城市的大部分家庭都使用天然气做饭。

Zhège chéngshì de dà bùfen jiātíng dōu shǐyòng tiānránqì zuòfàn.

Most households in this city use natural gas for cooking.

相比煤炭，天然气燃烧更干净，对环境的污染更小。

Xiāngbǐ méitàn, tiānránqì ránshāo gèng gānjìng, duì huánjìng de wūrǎn gèng xiǎo.

Compared with coal, natural gas burns more cleanly and causes less pollution to the environment.