屋子 (wūzi) means "room" or "house," referring to an enclosed living space. It is a colloquial term commonly used in spoken Chinese and is interchangeable with 房间 in many contexts. It often implies a smaller, more personal space.
这间屋子虽然小,但是很温馨。
Zhè jiān wūzi suīrán xiǎo, dànshì hěn wēnxīn.
This room is small, but it's very cozy.
请把屋子收拾一下,客人快到了。
Qǐng bǎ wūzi shōushi yíxià, kèrén kuài dào le.
Please tidy up the room; the guests will be here soon.
他一个人坐在屋子里看书。
Tā yí ge rén zuò zài wūzi lǐ kàn shū.
He sat alone in the room reading a book.