Future Subjunctive in Portuguese

Overview

Future Subjunctive (Conjuntivo Futuro) is a upper-intermediate (CEFR B2) topic in Portuguese grammar. Unique to Portuguese: future subjunctive for uncertain future. From third person plural preterite stem: -ar→-ar, -er/-ir→-er/-ir. Used with quando, se, enquanto, assim que for future.

Understanding future subjunctive is essential for building correct Portuguese sentences and communicating effectively. This concept is introduced at the B2 level and forms part of the foundation for more advanced grammar structures.

Whether you are learning Brazilian or European Portuguese, mastering future subjunctive will significantly improve your ability to express yourself naturally and accurately in a variety of contexts.

How It Works

Formation: Same preterite stem as imperfect subjunctive, different endings:

Infinitive	3rd pl. pret.	Fut. subj. (eu)
falar	falaram	falar
comer	comeram	comer
ser/ir	foram	for
ter	tiveram	tiver
fazer	fizeram	fizer
poder	puderam	puder

Endings: -r, -res, -r, -rmos, -rdes, -rem.

Used after: quando (when), se (if), enquanto (while), assim que (as soon as), depois que (after) -- all referring to the future. Unique to Portuguese among modern Romance languages.

Examples in Context

Portuguese	English	Note
Quando chegares, telefona-me.	When you arrive, call me.
Se tiver tempo, irei.	If I have time, I'll go.
Enquanto viveres...	As long as you live...
Assim que puder, farei.	As soon as I can, I'll do it.
Se tiveres tempo.	If you have time.
Enquanto eu viver.	As long as I live.
Logo que puder.	As soon as I can.
Se for possivel.	If possible.
Quem quiser pode ir.	Whoever wants can go.

Common Mistakes

Using the wrong tense for the context

• Wrong: Choosing a different past or future tense when future subjunctive is required
• Right: Identify the specific temporal meaning before selecting the tense
• Why: Each Portuguese tense carries a distinct meaning about when and how an action occurred. Future Subjunctive is used in specific contexts that differ from related tenses.

Forgetting irregular forms

• Wrong: Applying regular conjugation patterns to irregular verbs
• Right: Memorize the irregular forms for common verbs in this tense
• Why: Many of the most frequently used Portuguese verbs are irregular and must be learned individually.

Mixing up register levels

• Wrong: Using very formal tense forms in casual conversation
• Right: Match your tense choice to the formality of the situation
• Why: Some forms are more common in speech while others are preferred in writing. Using the wrong register can sound awkward.

Usage Notes

At the B2 level, understanding regional variation becomes more important. Brazilian and European Portuguese may handle future subjunctive differently in terms of frequency, formality, and preferred constructions.

This concept is essential for both spoken and written Portuguese at the intermediate level. In formal writing, adhere to the standard rules; in casual speech, you may encounter simplified or alternative forms, particularly in Brazilian Portuguese.

Practice Tips

1. Practice future subjunctive with authentic Portuguese texts, listening for how native speakers use these forms in context.
2. Create flashcards with complete example sentences rather than isolated words to reinforce natural patterns.
3. Write short paragraphs using future subjunctive and compare them with native-written texts to identify areas for improvement.

Related Concepts

• Prerequisite: Present Subjunctive -- provides the foundational knowledge needed for future subjunctive