unir Preterite Conjugation
unir — to join
Unir is regular in the preterite: uní, uniste, unió, unimos, unisteis, unieron.
unir Preterite Forms
When to Use the Preterite
Use the preterite when you finished joining something at a specific moment in the past, like when two companies merged or you glued two items together.
Notes on unir in the Preterite
Unir is regular in the preterite. Note that the 'nosotros' form is the same as the present tense; context is key.
Example Sentences
Ayer uní los cables del televisor.
Yesterday I joined the TV cables.
yo
Ellos unieron sus vidas en matrimonio.
They joined their lives in marriage.
ellos/ellas/ustedes
El arquitecto unió los dos edificios.
The architect joined the two buildings.
él/ella/usted
Common Mistakes
Mistake: unio
Correct: unió
Why: Forgetting the accent on the third-person singular is common, but it changes the pronunciation and tense.
Master Spanish verbs in context
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Related Tenses
Present
yo: uno
The present tense of unir is regular: uno, unes, une, unimos, unís, unen.
Imperfect
yo: unía
The imperfect of unir uses standard -ía endings: unía, unías, unía, uníamos, uníais, unían.
Future
yo: uniré
The future of unir is formed by adding endings to the infinitive: uniré, unirás, unirá, uniremos, uniréis, unirán.
Conditional
yo: uniría
The conditional of unir uses the infinitive plus -ía: uniría, unirías, uniría, uniríamos, uniríais, unirían.
Present Subjunctive
yo: una
The present subjunctive of unir follows the regular -ir pattern: una, unas, una, unamos, unáis, unan.
Imperfect Subjunctive
yo: uniera
The imperfect subjunctive of unir is regular: uniera, unieras, uniera, uniéramos, unierais, unieran.
Affirmative Imperative
yo: une
The imperative of unir gives direct commands: une (tú), unid (vosotros), una (usted).
Negative Imperative
yo: no unas
The negative imperative of unir uses the present subjunctive forms: no unas, no una, no unamos, no unáis, no unan.