introducir Preterite Conjugation
introducir — to put in
The preterite of introducir is irregular, replacing the 'c' with a 'j' (introduje, introdujiste, introdujo).
introducir Preterite Forms
When to Use the Preterite
Use the preterite for a completed action in the past, like when you inserted a key or introduced a friend at a specific party.
Notes on introducir in the Preterite
This is a 'j-stem' irregular verb. Note that the third-person plural ends in -eron, not -ieron.
Example Sentences
Introduje la llave, pero no giró.
I put the key in, but it didn't turn.
yo
Ella introdujo a su novio a la familia.
She introduced her boyfriend to the family.
él/ella/usted
Ellos introdujeron los cambios el lunes.
They introduced the changes on Monday.
ellos/ellas/ustedes
Common Mistakes
Mistake: introdujieron
Correct: introdujeron
Why: After a 'j' in the preterite, the 'i' in the -ieron ending is dropped.
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Related Tenses
Present
yo: introduzco
The present tense of introducir is irregular in the 'yo' form (introduzco), while the rest follow standard -ir patterns.
Imperfect
yo: introducía
The imperfect of introducir is completely regular: introducía, introducías, introducía.
Future
yo: introduciré
The future tense of introducir is regular: just add endings to the infinitive.
Conditional
yo: introduciría
The conditional of introducir is regular: introduciría, introducirías, etc.
Present Subjunctive
yo: introduzca
The present subjunctive uses the 'introduzc-' stem for all persons.
Imperfect Subjunctive
yo: introdujera
This tense uses the 'j' stem from the preterite: introdujera, introdujeras, etc.
Affirmative Imperative
yo: introduce
The imperative uses 'introduce' for 'tú' and 'introduzca' for formal commands.
Negative Imperative
yo: no introduzcas
The negative imperative always uses the 'introduzc-' stem from the subjunctive.