There are four kinds of words.
Agudas. The strong sylable is the last one. "cagó" Contains the mark ONLY if the last letter is a vowel, N or S.
Llanas/Graves. The strong sylable is the second last. "lápiz" Contains the mark ONLY if the last letter ISN'T a vowel, N or S.
Esdrújulas/Sobreesdrújulas. The strong sylable is anywhere except the last two.
The fourth kind is a special exception made with questions and pronouns.
Who can speak Yiddish?
I was taught hebrew the last two years of school. No yiddish though.