3 sentences

1. 你刚才说的简直是屁！

   nǐ gāng​cái shuō de jiǎn​zhí shì pì!

   What you just said is complete nonsense!

   Source: Dong Chinese Dictionary

2. 他忍不住放了一个屁。

   tā rěn bù zhù fàng le yī gè pì.

   He couldn't help but fart.

   Source: Dong Chinese Dictionary

3. 关于这件事，他懂个屁！

   guān​yú zhèi jiàn shì, tā dǒng gè pì!

   He knows jack shit about this!

   Source: Dong Chinese Dictionary