suponer Preterite Conjugation
suponer — to suppose
Suponer uses the irregular stem 'supus-' in the preterite: supuse, supusiste, supuso.
suponer Preterite Forms
When to Use the Preterite
Use the preterite when an assumption was made at a specific point in time or when something 'meant' or 'implied' a finished consequence.
Notes on suponer in the Preterite
This is a 'strong' preterite. The stem changes to 'supus-' and it uses the irregular endings -e, -iste, -o, -imos, -isteis, -ieron (no accents).
Example Sentences
Supuse que ya lo sabías.
I assumed you already knew it.
yo
¿Cómo supusiste la contraseña?
How did you guess the password?
tú
Ese error supuso el fin de su carrera.
That error meant the end of his career.
él/ella/usted
Common Mistakes
Mistake: Saying 'suponí' or 'suponió'.
Correct: Use supuse and supuso.
Why: Suponer follows the irregular pattern of 'poner', not the regular -er pattern.
Mistake: Adding accents to 'supuse' or 'supuso'.
Correct: These forms do not have accents.
Why: Strong preterites with irregular stems don't take accents on the final syllable.
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Related Tenses
Present
yo: supongo
Suponer follows the pattern of 'poner' in the present, with a 'go' ending in the yo form: supongo.
Imperfect
yo: suponía
Suponer is completely regular in the imperfect: suponía, suponías, suponía.
Future
yo: supondré
Suponer has an irregular stem in the future: supondré, supondrás, supondrá.
Conditional
yo: supondría
The conditional uses the same irregular stem as the future: supondría, supondrías.
Present Subjunctive
yo: suponga
The present subjunctive is built from the 'yo' form 'supongo': suponga, supongas, suponga.
Imperfect Subjunctive
yo: supusiera
Based on the preterite 'supusieron', the stem is 'supusiera-'.
Affirmative Imperative
yo: supón
The command for 'tú' is 'supón'; other forms use the 'supong-' stem.
Negative Imperative
yo: no supongas
The negative command uses 'no' plus the present subjunctive: no supongas, no suponga.