老师让我录一段自我介绍。

Lǎoshī ràng wǒ lù yí duàn zìwǒ jièshào.

The teacher asked me to record a short self-introduction.

请把这首歌录下来给我听。

Qǐng bǎ zhè shǒu gē lùxiàlái gěi wǒ tīng.

Please record this song for me to listen to.

老师让我们把自己的发音录下来，再听一听。

Lǎoshī ràng wǒmen bǎ zìjǐ de fāyīn lù xiàlai, zài tīng yì tīng.

The teacher asked us to record our own pronunciation and then listen to it.