What else did he do?
other可作形容词或代词,做形容词时,意思是“别的,其他”,泛指“其他的（人或物）”.如：
Do you have any other question(s)?
Ask some other people.
问问别人吧!
Put it in your other hand.
把它放在你另一只手里.
else表示“另外的”表示“除此之外 ,还有”,相当于besides,如：
What else can I say?
我还能说什么呢?