Changes in vowel quality

Vowels e and o may change vowel quality along the presente do indicativo, presente do subjuntivo, imperativo afirmativo and imperativo negativo in certain environments.

Closed vowels e and o that precede the infinitive ending -ar become open vowels (e as in get and o as in hot) in the persons that have been highlighted:

Remember:

Vowels e and o are always closed in the infinitive.

Vowels e and o are always closed in the persons nós and vós of all verb tenses.

Vowels e and o are closed in all persons of the other verb tenses.

These guidelines apply to verbs of the three conjugations.

There aren't changes in vowel quality (the vowels are closed) along conjugations when:

• Vowels e and o are followed by m, n, lh or nh;

• Vowels e and o are followed by i;

• Vowel e is followed by x, ch and j.

• Verbs in -oar

Examples

These rules cover most verbs in the language; an important exception, however, is verb chegar (verb to arrive), of which all verb tenses, in all persons, have a closed e: