Categories
There are four categories of accents:
Aguda
This is when the emphasis is on the last syllable.
Include an Accent
Ending in n/s/vowel
Don't Include an Accent
Everything else
Examples:
Papel, español, francés, común, ciudad
Llana
This is when the emphasis is on the second to last syllable. Here the rule is switched from aguda.
Include an Accent
Everything else
Don't Include an Accent
Ending in n/s/vowel
Examples:
- Como
- lunes
- examen
- carácter
- lápiz
Esdrújula/Sobreesdrújula
This means 3rd to last/4th to last emphasis. You always add an accent in this case.
Examen -> Exámenes
Estúpido
Monólogo
Vendámoselo
Special Rules
Verb -> Adverb
When you convert a verb into an adverb, the accents remain.
Lento -> Lentamente
Rápido -> Rápidamente
Qué/Dónde/Cómo/Quién/Cuántos/Cuándo
When one of these words are in a question, there is an accent. Additionally, when a sentence is a response to a question, you also include the accent. Here are a few examples:
No sabía qué hacer. In this example, qué maintains the use that it would have in a question: what? I didn't know what to do. Que without an accent means "that", "which",or "who".
No sé cómo llegó. In this example, cómo maintains the question definition. Como without an accent would mean "like", such as "Trabaja como yo."
No sé cuántos dólares cuesta el coche. In this example, cuántos is used to mean "how many".
Hopefully, you understand the pattern. Removing the accent changes the meaning of the word slightly. Keeping the accent keeps the question-like meaning.