Breakdown of Vem buade publiken åt?
vem
who
publiken
the audience
bua
to boo
åt
at (directed at, e.g. laugh/boo at)
Questions & Answers about Vem buade publiken åt?
Where would I put inte ens if I wanted to ask 'Who didn't the audience even boo at?'
In a main clause question like this, sentence adverbials like inte ens go right after the subject. Since publiken is the subject, you would say: Vem buade publiken inte ens åt?
Why is åt at the very end of the sentence?
Swedish, just like English, frequently uses 'preposition stranding.' Because the question word Vem is the object of the preposition åt, the preposition gets left at the end of the clause. You could technically say Åt vem buade publiken? (At whom did the audience boo?), but leaving åt at the end is much more natural in spoken Swedish.
Why do we use åt for 'at' here instead of på?
While på often translates to 'at' (like in titta på, to look at), verbs expressing an emotional reaction or facial expression directed towards someone typically use åt. Just as you say skratta åt (laugh at) or le åt (smile at), the standard phrase here is att bua åt (to boo at).
Is buade a regular verb?
Yes, it is a regular Group 1 verb: att bua (to boo). Because the infinitive ends in an 'a', it simply takes the standard -de ending in the past tense, forming buade.