what (EN)
pronoun, determiner, interjection

pronoun “what”

what
  1. used to ask about the identity, quantity, or quality of something
    What did you have for breakfast this morning?
  2. that which (connects a dependent clause with the main clause)
    I know what you did.
  3. whatever
    Take what you need from the fridge.

determiner “what”

what
  1. used to ask about one or more possibilities from a set
    What kind of music do you like?
  2. specifies the particular thing(s) that
    She couldn't decide what dress to wear to the party.
  3. refers to any or all things of a certain type
    She gave away what little money she had to help the homeless.
  4. highlights the extent or degree of something
    She showed me what an incredible singer she is with her stunning performance.

interjection “what”

what
  1. a direct question asking someone's purpose or desire, often unfriendly
    What? I don't have time right now.
  2. a request for repetition or clarification of what was said
    — I think I left my keys in the, uh, thingamajig over there., — What? Can you be more specific?
  3. an exclamation of astonishment or disbelief
    What? You won the lottery?
  4. used when making a guess, approximation, or trying to remember something
    He's been working there for, what, ten years now?