知晓

tā de sǐ yīn yě xǔ wú rén zhī xiǎo

她的死因也许无人知晓。

How she met her death will probably never be known.

jiū jìng fā shēng le shén me wú rén zhī xiǎo

究竟发生了什么无人知晓。

Exactly what transpired remains unknown.