他们家新买了一套沙发，放在客厅里很漂亮。

Tāmen jiā xīn mǎi le yī tào shāfā, fàng zài kètīng lǐ hěn piàoliang.

Their family just bought a new sofa set — it looks beautiful in the living room.

我想买一套西装参加婚礼。

Wǒ xiǎng mǎi yī tào xīzhuāng cānjiā hūnlǐ.

I want to buy a suit to attend a wedding.

这套书一共有十二本，我都看完了。

Zhè tào shū yīgòng yǒu shí'èr běn, wǒ dōu kàn wán le.

This set of books has twelve volumes in total, and I've finished reading all of them.