火 (huǒ) means fire. It is a basic vocabulary word used in many compound words such as 火山 (volcano), 火车 (train), and 火灾 (fire disaster). On its own, it refers to flames or combustion.
小心,锅里的火太大了,菜要烧焦了。
Xiǎoxīn, guō lǐ de huǒ tài dà le, cài yào shāojiāo le.
Be careful, the flame under the pot is too high — the food is about to burn.
冬天的时候,我们喜欢在院子里生火取暖。
Dōngtiān de shíhou, wǒmen xǐhuan zài yuànzi lǐ shēnghuǒ qǔnuǎn.
In winter, we like to make a fire in the yard to keep warm.
消防员花了三个小时才把火扑灭。
Xiāofángyuán huā le sān ge xiǎoshí cái bǎ huǒ pūmiè.
It took the firefighters three hours to put out the fire.