Learn Spanish (Spain): El río va al mar. - The river goes to the sea.

In Spanish, when the preposition a (to) comes right before the masculine word el (the), they mash together to form al. This is a mandatory contraction, so you can never say a el unless El is part of a proper name. Since mar is masculine (el mar), we use al.

Where does the word va come from?

va is the he/she/it form of the verb ir (to go). ir is a highly irregular verb, which is why va doesn't look anything like its infinitive (dictionary) form. Here, it matches El río (The river), which acts as a third-person subject.

Why does río have an accent mark?

The accent on the i in río tells you to put the stress on that letter. Without the accent mark, the i and o would blend together into a single syllable. The accent breaks them apart into two distinct syllables: REE-o.

How do we know if mar is masculine or feminine here?

We know it is masculine because we used the word al, which is a combination of a and el (the masculine word for the). While you might occasionally hear la mar in poetry or sailing contexts, in everyday Spanish, mar is treated as a masculine noun.