Breakdown of Welk station is dit?
zijn
to be
dit
this (neuter)
het station
the station
welk
which (for het-words)
Questions & Answers about Welk station is dit?
Why is it welk and not welke in this sentence?
Because station is a het word (het station). When asking 'which' about a singular het word, you use welk. If it were a de word or a plural word, you would use welke.
Why does the verb is come after station? I thought verbs come first in questions?
In yes/no questions, the verb comes first. But when you use a question word, the question phrase goes first, and the verb comes second. Here, the entire phrase welk station acts as the first block, so the verb is takes the second spot right after it.
Could I say welk station is dat if I mean 'that station'?
Yes! Dit means 'this' (close to you) and dat means 'that' (further away). Since you are usually standing right at or inside the station when asking this, dit makes the most sense here.