alterar Imperfect Subjunctive Conjugation
alterar — to change
The imperfect subjunctive of alter (alterara/alterase) is used for past hypotheticals, wishes, or polite requests.
alterar Imperfect Subjunctive Forms
When to Use the Imperfect Subjunctive
This tense is perfect for talking about hypothetical situations in the past, or expressing wishes and doubts that were relevant in the past. For example, 'Si alterara las reglas, habría un problema' (If I were to change the rules, there would be a problem). It’s also used for polite requests in the past.
Notes on alterar in the Imperfect Subjunctive
Alter is regular in the imperfect subjunctive. Both the -ra and -se forms are correct, though the -ra form (alterara, alteraras, etc.) is more common in many regions. Just pick one and stick with it!
Example Sentences
Si yo alterara las condiciones, ¿estarías de acuerdo?
If I were to change the conditions, would you agree?
yo
Me pidió que no alterase el documento.
He asked me not to change the document.
yo
Era importante que él alterara su opinión.
It was important that he change his opinion.
él/ella/usted
Ojalá alteráramos la rutina un poco más.
I wish we would change the routine a bit more.
nosotros
No creía que ellos alteraran el resultado.
I didn't think they would change the result.
ellos/ellas/ustedes
Common Mistakes
Mistake: Using the imperfect indicative instead of the imperfect subjunctive.
Correct: Use 'alterara' or 'alterase' after 'si' for hypotheticals, not 'alteraba'.
Why: The imperfect subjunctive is required for hypothetical conditions in the past, whereas the imperfect indicative describes ongoing past actions.
Mistake: Confusing the -ra and -se endings.
Correct: Both 'alterara' and 'alterase' are correct forms of the imperfect subjunctive. Choose one style.
Why: While both are grammatically correct, consistency is key. Regional preferences exist, but learners should just pick one.
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Related Tenses
Present
yo: altero
The present tense of alter (altero, alteras, altera, alteramos, alteráis, alteran) describes current actions, habits, or general truths.
Preterite
yo: alteré
The preterite of alter is regular: alteré, alteraste, alteró, alteramos, alterasteis, alteraron.
Imperfect
yo: alteraba
The imperfect of alter (alteraba, alterabas, alteraba, alterábamos, alterabais, alteraban) describes ongoing or habitual past actions.
Future
yo: alteraré
The future tense of alter (alteraré, alterarás, alterará, alteraremos, alteraréis, alterarán) indicates actions that will happen.
Conditional
yo: alteraría
The conditional of alter (alteraría, alterarías, alteraría, alteraríamos, alteraríais, alterarían) expresses hypotheticals ('would') and polite requests.
Present Subjunctive
yo: altere
The present subjunctive of alter (altere, alteres, alteremos, alteréis, alteren) is used after expressions of will, doubt, emotion, and uncertainty.
Affirmative Imperative
yo: altera
Alter commands are mostly regular: ¡altera, altere, alteremos, alterad, alteren!
Negative Imperative
yo: no alteres
Negative commands for alter are formed with 'no' + present subjunctive: no alteres, no altere, no alteremos, no alteréis, no alteren.