To classify the words, you have to divide the word in syllables and focus on the force of pronunciation. If the force of pronunciation is on last syllable, it's Aguda. If it's on the second to last syllable it's Llana. If it's on the third to last syllable, it's Esdrujula. And if it's on the fourth to last syllable, it's Sobreesdrújula.
Remember: If the word has an accent it's easier to identify. If it doesn't have an accent, try finding which syllable sounds better with the force of pronunciation.
