咋(zǎ) - how, why, what (colloquial, northern dialect) in Mandarin

咋 (ză) is 怎么 with its sleeves rolled up. It means how or why, it is northern, and it is thoroughly colloquial: 咋办, 咋样, 咋回事, 你咋了.

You will hear it constantly in the northeast and across the north, and you will read it in subtitles, chat messages and internet comments, where it carries a warm, blunt, unbuttoned tone. A newsreader will not use it.

The trap is register rather than meaning. Write 咋 in an email to a teacher or a client and it lands like writing gonna in a covering letter. Understand it everywhere, use it with friends, and reach for 怎么 whenever the situation has any formality in it at all.