"There are many nice red apples at the market."
Translation:Van sok szép piros alma a piacon.
Sentences can start with a verb if you want to put emphasis on the action itself. (Usually you'd use a preverb for that, but van doesn't like preverbs.) Here you're asking what the apples are doing - well, they simply exist. It's a rather odd construction.
Later in the course there's the sentence "Van valami a mellén?" - "Is there something on her breast?" (or similar, I don't remember the exact wording), where a construction like this works much better. You're asking about the existence of "something" - is it there? Yes or no?