Hola Colin

As explained in the lesson the verb gustar (to like) works differently to other verbs.

The subject of "gustar" is "whatever the person likes". This can be a singular thing or a plural thing. 

Then the verb gustar agrees with that subject. It is either "gusta" for a singular thing or "gustan" for a plural thing. Then the person doing the liking is expressed with "me, te, le..." (these are called indirect object pronouns). So:

It is as if we were saying "the city pleases me" and "Apples please me". This way you can see the subject, the verb and the indirect object more clearly.

I hope this clarified it.

Saludos

Inma