Answer:
agudas -- are words whose ultimate (last) syllable is stressed
llanas -- refer to words whose penultimate (second-to-last) syllable is stressed
esdrújulas -- refers to words whose antepenultimate (third-to-last) syllable is stressed
Step-by-step explanation:
examples:
agudas ----- hablar, melón
llanas ----- árbol, mesa
esdrújulas ----- número, pájaro