ACCENT is the greatest effort we make to pronounce a certain syllable of a word. When we say ,, , we can not help noticing that the intensity with which we articulate the syllables ral, plu and can is superior to the one we use to pronounce the remaining syllables. Accent is also called an inclined line from right to left (´) with which we sometimes indicate in writing that greater intensity or effort. To distinguish one from the other, this last accent is called orthographic, unlike the first, commonly known as the prosodic accent.

As far as the accent is concerned, the words are divided into agudas, graves, esdrújulas and sobreesdrújulas. The words that carry the accent on the last syllable are agudas: , , , , ; those who have it in the penultimate graves: , , , , ; those that are accentuated in the antepenultimate esdrújulas: , ,; those that appear accented in any syllable previous to the antepenultimate sobreesdrújulas: , .

Almost all the compound words have two prosodic accents, in virtue of which the immense majority of them only consist, in Spanish, of two component elements; v. gr. : , . And there are also words, like monosyllables, that lack a prosodic accent; v. gr.: ,, , , , , , , , , .

Carlos González Peña, Manual de Gramática Castellana. Editorial Patria, S.A.(Textual)