4 sentences

1. 白云在蓝天中悠悠地飘荡。

   bái​yún zài lán​tiān zhōng yōu​yōu de piāo​dàng.

   White clouds float leisurely in the blue sky.

   Source: Dong Chinese Dictionary

2. 悠悠岁月，承载着无数的回忆。

   yōu​yōu suì​yuè, chéng​zài zhe wú​shù de huí​yì.

   The long years carry countless memories.

   Source: Dong Chinese Dictionary

3. 这完全是悠悠之谈，不足为信。

   zhè wán​quán shì yōu​yōu zhī tán, bù​zú wéi xìn.

   This is completely baseless talk and is not to be believed.

   Source: Dong Chinese Dictionary

4. 每当听到这首老歌，他心中总会产生悠悠的思念。

   měi​dāng tīng​dào zhè shǒu lǎo gē, tā xīn​zhōng zǒng​huì chǎn​shēng yōu​yōu de sī​niàn.

   Whenever he hears this old song, a lingering sense of longing arises in his heart.

   Source: Dong Chinese Dictionary