我困了，想睡觉。

Wǒ kùn le, xiǎng shuìjiào.

I'm sleepy, I want to sleep.

我每天晚上十二点前睡觉。

Wǒ měitiān wǎnshang shí'èr diǎn qián shuìjiào.

I go to sleep before 12 every night.

我习惯睡觉前听一点音乐。

Wǒ xíguàn shuìjiào qián tīng yìdiǎn yīnyuè.

I'm used to listening to music before falling alseep.