Rules for Accentuation

Remember that if a word ends in an 'n' , 's' or a vowel, then the natural stress will fall on the next to last syllable.

If a word ends in a consonant other than 'n' or 's', then the natural stress falls on the last syllable.

Words that do not follow the natural stress pattern require a written accent to show which vowel should be stressed.

Keeping in mind the rules of natural stress, consider what happens when we attach a pronoun to an affirmative command.

For example, the command form 'Come' is stressed on the next to last syllable, so no accent mark is needed. However, if we say 'Cómela' then a written accent is needed to show that the stress is on the 'o' rather than on the next to last syllable. No matter how many pronouns you add to the end of an affirmative command, the accented vowel should be the same one that is stressed when the command has no pronouns attached:

Toma Take	Tómalas Take them (the 'las' could represent 'las pastillas')
Explique Explain	Explíquemelo Explain it to me

Be careful with the irregular affirmative commands like di, ten, pon, etc. No accent is needed if you add just one pronoun since the word still follows the natural stress pattern:

Di Tell

Dila Tell it (the 'la' could represent 'la verdad')

You will need an accent mark when adding 2 pronouns, since now the word doesn't follow the natural stress pattern:

Dímela Tell it to me