alterar Negative Imperative Conjugation
alterar — to change
Negative commands for alter are formed with 'no' + present subjunctive: no alteres, no altere, no alteremos, no alteréis, no alteren.
alterar Negative Imperative Forms
When to Use the Negative Imperative
Use the negative imperative to tell someone not to do something. It's like a prohibition or a warning. For example, 'No alteres el documento original' means 'Don't change the original document'.
Notes on alterar in the Negative Imperative
Alter is regular in the negative imperative, which is formed using the present subjunctive. This means the forms for 'usted', 'nosotros', and 'ustedes' are the same as the positive imperative, just preceded by 'no'.
Example Sentences
No alteres la configuración sin permiso.
Don't change the settings without permission.
tú
No altere los datos personales.
Do not change the personal data.
usted
No alteremos el curso de los acontecimientos.
Let's not alter the course of events.
nosotros
¡No alteréis la estructura del informe!
Don't change the report's structure!
vosotros
No alteren las conclusiones del estudio.
Do not change the study's conclusions.
Common Mistakes
Mistake: Using the infinitive instead of the subjunctive.
Correct: Use 'no alterar' for the infinitive, but for commands, use 'no alteres' (tú) or 'no altere' (usted).
Why: Negative commands require the subjunctive mood, not the infinitive.
Mistake: Confusing with the affirmative imperative.
Correct: Remember the 'no' is crucial: 'Altera' (change it) vs 'No alteres' (don't change it).
Why: The presence or absence of 'no' completely changes the meaning from a command to a prohibition.
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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.
Imperfect Subjunctive
yo: alterara
The imperfect subjunctive of alter (alterara/alterase) is used for past hypotheticals, wishes, or polite requests.
Affirmative Imperative
yo: altera
Alter commands are mostly regular: ¡altera, altere, alteremos, alterad, alteren!