Learn Polish: Ten wysoki mur może całkowicie zakryć widok. - This high wall can completely block the view.

The base verb kryć means "to cover" or "to hide." By adding the prefix za-, which often denotes blocking or enclosing, we get zakryć. Here, it means to cover something up to the point of acting as a barrier, effectively "blocking" the view completely.

Could I use the verb zasłonić here instead?

Yes, absolutely! Zasłonić widok is a very natural and common collocation in Polish for "to block the view." Notice that zasłonić also uses the exact same za- prefix to convey the idea of putting up a visual barrier.

Why do we use the perfective verb zakryć instead of an imperfective form like zakrywać?

We use the perfective zakryć because the sentence describes a complete, successful action. The wall has the potential to completely block the view once and for all, focusing on the final result rather than the ongoing process of covering.

Since widok is the direct object being blocked, why doesn't its ending change?

As the direct object, widok is indeed in the accusative case. However, because it is a masculine inanimate noun (like a table, a house, or a view), its accusative form is identical to its nominative form. That is why it doesn't take a typical accusative ending like -a or -ę.