It seems odd to introduce "whose" and the different-from-English fact that shoes are a collective noun in Hungarian (and so, not plural). Why not introduce "kinek" first with a noun that has a more direct translation so there is only one new concept at a time?

Wait - before cipo was "shoes" - now it has reverted to the singular? Why?

There is no consistency and the creators break their own rulers. We know that cipő is shoes. In Hungarian it can be either a single shoe or the pair, but then every exercise my allow the use of these translations. Bear in mind that unless it is clearly indicated, in English always that we say shoes we refer to the pair of shoes.