3 sentences

1. 我相信他上辈子一定是只猫。

   wǒ xiāng​xìn tā shàng bèi​zi yī​dìng shì zhī māo.

   I think in another life, he must have been a cat.

   Source: OpenSubtitles

2. 我上辈子一定欠了你很多钱。

   wǒ shàng​bèi​zi yī​dìng qiàn le nǐ hěn​duō qián.

   I must have owed you a lot of money in my previous life.

   Source: Dong Chinese Dictionary

3. 他常开玩笑说，自己上辈子可能是一只猫。

   tā cháng kāi​wán​xiào shuō, zì​jǐ shàng​bèi​zi kě​néng shì yī zhī māo.

   He often jokes that he might have been a cat in a previous life.

   Source: Dong Chinese Dictionary