You can pick your friends, and you can pick your nose, but you can't pick your friend's nose.

You can pick your friends, and you can pick your nose, but you can't pick your friend's nose.

你可以选择你的朋友，你可以选择你的鼻子，但是你不能选择你朋友的鼻子。

-- John Green 约翰·格林