The future subjunctive: Core irregulars

Irregular Future Subjunctive

You already know that the Future Subjunctive is used with conjunctions like se, quando, and assim que to talk about probable future events. However, some of the most common verbs in Portuguese are irregular in this mood.

To find the base for an irregular verb in the future subjunctive, look at its eles/elas form in the simple past (Pretérito Perfeito), and drop the -am ending. Then, add the regular future subjunctive endings:

The Verb "ter"

The simple past of ter (to have) is tiveram. Dropping the -am gives us the base tiver-.

The Verb "haver"

To say "if there is" or "when there are" in the future, use the verb haver. Its past tense base is houveram, so the future subjunctive form is houver. Because it means "there is/are", you will almost always use it in the singular ele/ela form.

The Verb "estar"

The past tense of estar (to be - temporary) is estiveram, giving us the base estiver-.

The Verbs "ser" and "ir"

Just like in the simple past, the verbs ser (to be - permanent) and ir (to go) share the exact same forms. Their past tense base is foram, giving us the base for-. You will know which verb is being used based on the context.