-a/-as/-a/-amos/-ais/-am
Presente Do Subjuntivo -ER/-IR
The Present Subjunctive for -ER and -IR verbs uses the vowel -a- (the 'polarity flip'). It is triggered by verbs of emotion, doubt, or specific conjunctions.
How It Works
The Presente do Subjuntivo is a grammatical mood required when a sentence is filtered through subjectivity. For verbs ending in -ER and -IR, the characteristic vowel 'flips' from the indicative -e/-i to the subjunctive -a.
1. Formation Rule:
For all regular and stem-changing verbs, start with the 1st person singular (eu) of the Present Indicative to capture the stem.
- Comer (eu como) → com- + a = que eu coma
- Dormir (eu durmo) → durm- + a = que eu durma
Note: High-frequency irregulars like ser, ir, and saber do not follow this rule.
2. The Subject Change Rule:
The subjunctive is typically used when there are two different subjects. If the subject remains the same, we usually use the infinitive:
- Same Subject: Eu quero comer (I want to eat).
- Different Subjects: Eu quero que você coma (I want you to eat).
3. Usage Triggers:
It is commonly used after:
- Verbs of desire: Quero que...
- Verbs of doubt or uncertainty: Duvido que... or the adverb Talvez (Talvez ele venha).
- Impersonal expressions: É necessário que...
- Conjunctions: Para que... or Embora...
Examples (4)
- Duvido que eles bebam tanto café.
I doubt that they drink so much coffee.
Word by Word: I-doubt that they drink so-much coffee.
The verb 'beber' (-ER) changes its ending to -am because 'duvidar que' triggers the subjunctive.
- É importante que você durma bem.
It is important that you sleep well.
Word by Word: It-is important that you sleep well.
The verb 'dormir' (-IR) uses the stem 'durm-' from the 'eu' form (eu durmo) and adds the subjunctive ending -a.
- Espero que nós compreendamos a lição.
I hope that we understand the lesson.
Word by Word: I-hope that we understand the lesson.
The verb 'compreender' (-ER) takes the -amos ending in the subjunctive.
- Vou explicar de novo para que vocês não se percam.
I will explain again so that you don't get lost.
Word by Word: I-go to-explain of new for that you not yourself lose.
The conjunction 'para que' (so that) always requires the subjunctive.
Common Mistakes
Using the indicative ending (-e) instead of the subjunctive (-a) for -ER/-IR verbs.
Espero que ele come tudo.Espero que ele coma tudo.Learners often use 'come' because it is the standard -ER ending, but the subjunctive requires the 'polarity flip' to -a.
Failing to use the irregular 'eu' stem from the present indicative.
Talvez ele faza o bolo.Talvez ele faça o bolo.The stem must come from 'eu faço' (indicative), not the infinitive 'fazer'.
How It Connects
Learn This First
To form the present subjunctive for -ER and -IR verbs, learners must first be comfortable with the present indicative stems of these verbs. The subjunctive mood in Portuguese follows a 'vowel swap' rule: while -AR verbs use -E endings, -ER and -IR verbs use -A endings. Understanding the indicative forms and the basic concept of the subjunctive mood is necessary before learning these specific endings.
- -o/-es/-e/-imos/-is/-emPresent Tense -IR Verbs
Understanding the regular present indicative of -IR verbs is essential because the present subjunctive is formed by modifying the stem of the first person singular present indicative.
Level 1 - -e/-es/-e/-emos/-eis/-emPresente Do Subjuntivo -AR
Learning the subjunctive for -AR verbs first introduces the concept of the 'vowel swap' (where -AR verbs take -E endings and -ER/-IR verbs take -A endings), which is the core logic of the present subjunctive mood.
Level 3
Related Patterns
- querer que + SubjunctiveSubjuntivo Com Desejo
One of the most common triggers for using the present subjunctive.
Level 3 - duvidar que + SubjunctiveSubjuntivo Com Dúvida
A common trigger expressing uncertainty that requires this mood.
Level 3 - para que + SubjunctiveSo That (Purpose)
A conjunction of purpose that always triggers the subjunctive mood.
Level 5 - Sequence of Tenses (Present)
Explains how the present subjunctive relates to the tense of the main verb.
Level 5
Learn Next
Patterns that build on this one.
- fale/coma/partaImperativo Com VocêLevel 3
- falem/comam/partamImperativo Com VocêsLevel 3
- faça/faças/faça/façamos/façamSubjuntivo De FazerLevel 3
- não fales/não comas/não partasImperativo Negativo (Tu)Level 3
- que + SubjunctiveOrdens IndiretasLevel 3
- seja/sejas/seja/sejamos/sejamSubjuntivo De SerLevel 3
- tenha/tenhas/tenha/tenhamos/tenhamSubjuntivo De TerLevel 3
- tomara que + SubjunctiveTomara Com SubjuntivoLevel 3
And 3 more in the full list.
Words in This Pattern
Practice -a/-as/-a/-amos/-ais/-am in Bubblegum
Poppy, your AI tutor, writes Portuguese lessons at your level. Tap any grammar point in a lesson to see its full explanation.
