2 sentences for 腦後 (nǎo​hòu — back of the head)

1. 把右手放到脑后。

   bǎ yòu​shǒu fàng dào nǎo​hòu.

   Put your right hand behind your head.

   Source: OpenSubtitles

2. 把双手背在脑后，但不要拉你的脖子。

   bǎ shuāng​shǒu bèi zài nǎo​hòu, dàn bù​yào lā nǐ de bó​zi.

   Place your hands behind your head, but don’t pull on your neck.

   Source: CCMatrix