Breakdown of Hvad skal du bruge pengene til?
du
you
hvad
what
bruge
to use / to spend (money, time) / to need (together with the modal of obligation)
til
to (preposition) / for (purpose) / at (an event or occasion) / at (good at something)
Questions & Answers about Hvad skal du bruge pengene til?
Why is skal bruge translated as "need", and how is it different from har brug for?
While bruge literally means "use", the phrase skal bruge is highly idiomatic for "need" when talking about a practical requirement for a task. You already know har brug for (to need), which focuses more on a fundamental lack or dependency. Because this question asks about the practical application of the money, skal bruge sounds much more natural.
Does bruge always take til when saying what you use something for?
Yes, the verb bruge pairs with the preposition til to express purpose or function. The construction bruge noget til noget translates to applying something to a specific purpose, which fits perfectly when asking what the money is meant for here.
Why does the sentence end with til instead of putting it before hvad?
Just like in English ("What do you need the money for?"), Danish often places the preposition at the end of a question when the question word (Hvad) is the object of that preposition. You could technically say Til hvad skal du bruge pengene?, but leaving til at the end is the most natural word order in spoken Danish.
Why is "the money" translated as pengene instead of having a singular ending?