Learn Spanish (Latin America): Regreso al país. - I am returning to the country.

They would ask ¿Adónde regresas? (To where are you returning?). Because you are moving towards a destination, you use adónde instead of just dónde (where). The a (to) in adónde matches the a hidden inside al in this answer!

Why is it al país instead of a el país?

In Spanish, whenever the preposition a (to) comes right before the masculine word el (the), they squeeze together to form the contraction al. This is a mandatory rule, so you must always say al país.

Why isn't the word yo (I) at the beginning of the sentence?

The -o ending on the verb regreso already tells us exactly who is doing the action: I am. Because of this, the word yo is optional and usually dropped in everyday Spanish unless you really want to emphasize that you are the one returning.

Why does país have an accent mark?

The accent mark tells you to emphasize that vowel and breaks the a and i into two separate syllables: pah-EES. Without the accent mark, those vowels would blend together into a single syllable.