Putting accents to words in Spanish is very simple. It all depends on where the stress and what is the last letter in the word. According to stress, Spanish words are classified into three categories: agudas, llanas y esdrujulas.

"Agudas" words wear the stress on the last syllable (e.g. camión, reloj); "llanas" words wear the stress on the penultimate syllable (casa, árbol), and "esdrújulas" words wear the stress on the last before last or the third or further syllable beginning in the last (e.g. pájaro, célebre).

Now, as you can see, some of these words have an accent and others don't although the stress falls on the same syllable. How do I know when "agudas", "llanas" or "esdrujulas" should then wear an accent or not? It's very easy. You put the accent on a "aguda" word if that word ends in vowel, n or s (camión); you put the accent on a "llana" word if the word ends in any other letter except a vowel, n or s (árbol). Finally, all "esdrujulas" words carry an accent (e.g. pájaro, célebre).

Remember, only vowels carry accents, never the consonants!

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