2 sentences

1. 他不小心撞到了脑壳。

   tā bù xiǎo​xīn zhuàng​dào le nǎo​ké.

   He accidentally bumped his head.

   Source: Dong Chinese Dictionary

2. 动动你的脑壳，肯定能想出办法。

   dòng dòng nǐ de nǎo​ké, kěn​dìng néng xiǎng​chū bàn​fǎ.

   Use your head; you'll surely come up with a way.

   Source: Dong Chinese Dictionary