烧水的时候，壶嘴冒出了很多蒸气。

shāo shuǐ de shíhou, húzuǐ mào chū le hěn duō zhēngqì.

When boiling water, a lot of steam comes out of the spout.

水加热到一百度就会变成水蒸气。

shuǐ jiārè dào yì bǎi dù jiù huì biànchéng shuǐzhēngqì.

Water turns into steam when heated to one hundred degrees.

浴室里全是蒸气，镜子都看不清了。

yùshì lǐ quán shì zhēngqì, jìngzi dōu kàn bù qīng le.

The bathroom is full of steam; the mirror is all fogged up.