干什么

Why does 干什么 look like this?

This is a common phrase consisting of three parts: 1) 干 (gàn) - originally meaning 'shield' or 'dry', here it functions as a verb meaning 'to do'. 2) 什 (shén) - composed of the 'person' radical (人) and 'ten' (十), used as a placeholder in 'what'. 3) 么 (me) - a generic suffix for interrogative pronouns. Together, they form the most common way to ask 'What are you doing?' in Mandarin.