我要还钱给你。

Wǒ yào huánqián gěi nǐ.

I have to return money to you.

我还有很多作业没做。

Wǒ hái yǒu hěn duō zuòyè méi zuò.

I still have a lot of homework not done.

我把不合穿的衣服都退还了。

Wǒ bǎ bù héchuān de yīfu dōu tuìhuán le.

I returned all the clothes that didn't fit.