Definition
To be completely unable to understand something; to find something very confusing or nonsensical.
白话、看不懂
The contract is written so complexly that I can't make head nor tail of it.
合约写得太复杂了，我完全搞不懂。
I tried to understand the report, but the data and charts in it made me unable to make head nor tail of it.
我试着理解这份报告，但里面的数据和图表让我完全摸不着头脑。
I can't make head nor tail of her joke; I don't understand what's funny.
我听不懂她的笑话；我不知道哪里好笑。