怎么
zěn me
how?
what?; why?; variant of 怎麼|怎么[zen3 me5]
how (怎) + question softener (么) = how, what, why
The combination forms a complete question word asking 'how' or 'what' - 怎 carries the core interrogative meaning while 么 softens it into a natural spoken question. Together they create the most common way to ask about methods or reasons in Chinese.
你怎么来学校？
nǐ zěn me lái xué xiào ？
How do you come to school?
这个问题怎么这么难？
zhè ge wèn tí zěn me zhè me nán ？
Why is this problem so difficult?