虽然我曾失败过几次，但我没有放弃。

Suīrán wǒ céng shībài guò jǐ cì, dàn wǒ méiyǒu fàngqì.

Although I have failed several times, I have not given up.

我曾在北京学习过一年中文。

Wǒ céng zài Běijīng xuéxí guò yì nián Zhōngwén.

I once studied Chinese in Beijing for a year.

他曾说过要每天锻炼身体。

Tā céng shuō guò yào měitiān duànliàn shēntǐ.

He once said that he would exercise every day.