Sustituir Conjugation in Spanish
The Spanish verb sustituir means to substitute, and it is a verb you will use again and again once you know it. Sustituir means to substitute or to replace, and it is used for replacing a player, a teacher, a part and an ingredient: sustituir a un jugador, sustituir el azúcar. It takes a for the person replaced and por for the replacement. It is a -uir verb: yo sustituyo, él sustituye. Like every Spanish verb, sustituir changes its ending for each person and tense, and this page gives you the complete picture: every tense, every person, the gerund and the past participle, all from the verified conjugation tables. For example, in the present tense you say sustituyo a un jugador lesionado, and in the preterite you say sustituí al profesor enfermo. Work through the tables below, read the notes for each tense, and then test yourself with the examples, the common mistakes and the quiz at the end of the page.
Quick facts
- Infinitive: sustituir
- English: to substitute
- Verb type: irregular verb
- Ending: -ir
- Gerund: sustituyendo
- Past participle: sustituido
- Auxiliary verb: haber (all perfect tenses are formed with haber + sustituido)
- Pattern to learn: this verb is a -uir verb: the stem vowel i becomes y before a vowel ending, so the present is sustituyo and sustituye, and the gerund is sustituyendo.
Pronunciation is not listed on this page: the verified tables do not include IPA for sustituir, so no pronunciation is given rather than an invented one. Sustituir takes a for who is replaced and por for the replacement: sustituyo a Juan por Pedro.
Full conjugation tables
Every form below comes from the verified conjugation tables for sustituir. The imperfect subjunctive is shown in its -ra forms; the -se forms use the same stem. For reflexive verbs, the pronoun column shows the reflexive pronoun that goes before each form.
Present indicative
| Person | Form |
|---|---|
| yo | sustituyo |
| tú | sustituyes |
| él/ella/Ud. | sustituye |
| nosotros/as | sustituimos |
| vosotros/as | sustituís |
| ellos/ellas/Uds. | sustituyen |
Preterite
| Person | Form |
|---|---|
| yo | sustituí |
| tú | sustituiste |
| él/ella/Ud. | sustituyó |
| nosotros/as | sustituimos |
| vosotros/as | sustituisteis |
| ellos/ellas/Uds. | sustituyeron |
Imperfect
| Person | Form |
|---|---|
| yo | sustituía |
| tú | sustituías |
| él/ella/Ud. | sustituía |
| nosotros/as | sustituíamos |
| vosotros/as | sustituíais |
| ellos/ellas/Uds. | sustituían |
Future
| Person | Form |
|---|---|
| yo | sustituiré |
| tú | sustituirás |
| él/ella/Ud. | sustituirá |
| nosotros/as | sustituiremos |
| vosotros/as | sustituiréis |
| ellos/ellas/Uds. | sustituirán |
Conditional
| Person | Form |
|---|---|
| yo | sustituiría |
| tú | sustituirías |
| él/ella/Ud. | sustituiría |
| nosotros/as | sustituiríamos |
| vosotros/as | sustituiríais |
| ellos/ellas/Uds. | sustituirían |
Present perfect
| Person | Form |
|---|---|
| yo | he sustituido |
| tú | has sustituido |
| él/ella/Ud. | ha sustituido |
| nosotros/as | hemos sustituido |
| vosotros/as | habéis sustituido |
| ellos/ellas/Uds. | han sustituido |
Pluperfect
| Person | Form |
|---|---|
| yo | había sustituido |
| tú | habías sustituido |
| él/ella/Ud. | había sustituido |
| nosotros/as | habíamos sustituido |
| vosotros/as | habíais sustituido |
| ellos/ellas/Uds. | habían sustituido |
Future perfect
| Person | Form |
|---|---|
| yo | habré sustituido |
| tú | habrás sustituido |
| él/ella/Ud. | habrá sustituido |
| nosotros/as | habremos sustituido |
| vosotros/as | habréis sustituido |
| ellos/ellas/Uds. | habrán sustituido |
Conditional perfect
| Person | Form |
|---|---|
| yo | habría sustituido |
| tú | habrías sustituido |
| él/ella/Ud. | habría sustituido |
| nosotros/as | habríamos sustituido |
| vosotros/as | habríais sustituido |
| ellos/ellas/Uds. | habrían sustituido |
Present subjunctive
| Person | Form |
|---|---|
| yo | sustituya |
| tú | sustituyas |
| él/ella/Ud. | sustituya |
| nosotros/as | sustituyamos |
| vosotros/as | sustituyáis |
| ellos/ellas/Uds. | sustituyan |
Imperfect subjunctive (-ra)
| Person | Form |
|---|---|
| yo | sustituyera |
| tú | sustituyeras |
| él/ella/Ud. | sustituyera |
| nosotros/as | sustituyéramos |
| vosotros/as | sustituyerais |
| ellos/ellas/Uds. | sustituyeran |
Imperative (affirmative)
| Person | Form |
|---|---|
| tú | sustituye |
| él/ella/Ud. | sustituya |
| nosotros/as | sustituyamos |
| vosotros/as | sustituid |
| ellos/ellas/Uds. | sustituyan |
Imperative (negative)
| Person | Form |
|---|---|
| tú | sustituyas |
| él/ella/Ud. | sustituya |
| nosotros/as | sustituyamos |
| vosotros/as | sustituyáis |
| ellos/ellas/Uds. | sustituyan |
Gerund and past participle
| Form | Spanish | Use |
|---|---|---|
| Gerund | sustituyendo | with estar for the progressive: estoy sustituyendo |
| Past participle | sustituido | with haber for the perfect tenses: he sustituido |
How to use each tense
Present indicative
Use the present for routines, general facts and what is happening right now. Note the pattern here: this verb is a -uir verb: the stem vowel i becomes y before a vowel ending, so the present is sustituyo and sustituye, and the gerund is sustituyendo. For sustituir, the present looks like this in a real sentence: Sustituyo a un jugador lesionado. Learn the present forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Preterite
Use the preterite for finished actions with a clear end, often with ayer, el año pasado or anoche. Note the spelling change here: this verb is a -uir verb: the stem vowel i becomes y before a vowel ending, so the present is sustituyo and sustituye, and the gerund is sustituyendo. For sustituir, the preterite looks like this in a real sentence: Ayer, sustituí el azúcar por miel. Learn the preterite forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Imperfect
Use the imperfect for background, habits and actions in progress in the past, often with de niño, antes or mientras. For this verb the tense is regular, so the forms follow the standard endings for its verb class. For sustituir, the imperfect looks like this in a real sentence: De niño, sustituía al profesor enfermo. Learn the imperfect forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Future
Use the future for plans, predictions and promises, often with mañana, el año que viene or pronto. For this verb the tense is regular, so the forms follow the standard endings for its verb class. For sustituir, the future looks like this in a real sentence: Mañana, sustituiré una pieza rota del coche. Learn the future forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Conditional
Use the conditional for polite requests, hypotheticals and what would happen, often with si clauses. For this verb the tense is regular, so the forms follow the standard endings for its verb class. For sustituir, the conditional looks like this in a real sentence: Sustituiría a un jugador lesionado si pudiera. Learn the conditional forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Present perfect
Use the present perfect for recent actions and experiences, often with hoy, esta semana or ya. For this verb the tense is regular, so the forms follow the standard endings for its verb class. For sustituir, the present perfect looks like this in a real sentence: Hoy, he sustituido el azúcar por miel. Learn the present perfect forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Pluperfect
Use the pluperfect when one past action happened before another past action. For this verb the tense is regular, so the forms follow the standard endings for its verb class. For sustituir, the pluperfect looks like this in a real sentence: Había sustituido al profesor enfermo antes de salir. Learn the pluperfect forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Future perfect
Use the future perfect for something that will already be finished by a future time. For this verb the tense is regular, so the forms follow the standard endings for its verb class. For sustituir, the future perfect looks like this in a real sentence: Para mañana, habré sustituido una pieza rota del coche. Learn the future perfect forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Conditional perfect
Use the conditional perfect for what would have happened under different conditions. For this verb the tense is regular, so the forms follow the standard endings for its verb class. For sustituir, the conditional perfect looks like this in a real sentence: Habría sustituido a un jugador lesionado con más tiempo. Learn the conditional perfect forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Present subjunctive
Use the present subjunctive after expressions of wish, doubt, emotion and hope, such as espero que or quiero que. Note the spelling change here: this verb is a -uir verb: the stem vowel i becomes y before a vowel ending, so the present is sustituyo and sustituye, and the gerund is sustituyendo. For sustituir, the present subjunctive looks like this in a real sentence: Espero que él sustituya el azúcar por miel. Learn the present subjunctive forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Imperfect subjunctive (-ra)
Use the imperfect subjunctive after past wishes and in si clauses about the past, and note the -ra forms shown here; the -se forms use the same stem. For this verb the tense is regular, so the forms follow the standard endings for its verb class. For sustituir, the imperfect subjunctive looks like this in a real sentence: Si él sustituyera al profesor enfermo, todo cambiaría. Learn the imperfect subjunctive forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Imperative (affirmative)
Use the affirmative imperative for direct commands, instructions and invitations. Note the spelling change here: this verb is a -uir verb: the stem vowel i becomes y before a vowel ending, so the present is sustituyo and sustituye, and the gerund is sustituyendo. For sustituir, the affirmative imperative looks like this in a real sentence: ¡Sustituye una pieza rota del coche! Learn the affirmative imperative forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Imperative (negative)
Use the negative imperative, always with no, to tell someone not to do something. Note the spelling change here: this verb is a -uir verb: the stem vowel i becomes y before a vowel ending, so the present is sustituyo and sustituye, and the gerund is sustituyendo. For sustituir, the negative imperative looks like this in a real sentence: No sustituyas a un jugador lesionado. Learn the negative imperative forms in the table above alongside this example, and notice how the ending, not the stem, usually carries the meaning of the tense.
Example sentences
Ten natural sentences with sustituir, covering different tenses and persons. Each one uses a form from the tables above.
- Sustituyo a un jugador lesionado. — I substitute an injured player.
- Sustituye el azúcar por miel. — He/she substitutes sugar with honey.
- Ayer, sustituí al profesor enfermo. — Yesterday, I substituted the ill teacher.
- Antes, nosotros sustituíamos una pieza rota del coche. — Before, we used to substitute a broken car part.
- Mañana, tú sustituirás a un jugador lesionado. — Tomorrow, you will substitute an injured player.
- Yo sustituiría el azúcar por miel si tuviera más tiempo. — I would substitute sugar with honey if I had more time.
- Él ha sustituido al profesor enfermo. — He has substituted the ill teacher.
- Espero que él sustituya una pieza rota del coche. — I hope he substitutes a broken car part.
- Yo ya había sustituido a un jugador lesionado antes de salir. — I had already substituted an injured player before leaving.
- Ellos sustituían el azúcar por miel cuando eran jóvenes. — They used to substitute sugar with honey when they were young.
Common mistakes
- Wrong: Yo sustituye a un jugador lesionado. — Right: Yo sustituyo a un jugador lesionado. — The person matters: sustituye is the él/ella/Ud. form, while the yo form is sustituyo. Using the third-person form with yo is one of the most common beginner errors.
- Wrong: Yo sustituo el azúcar por miel. — Right: Yo sustituyo el azúcar por miel. — Sustituir is a -uir verb: the stem vowel i becomes y before a vowel ending, so the present is sustituyo and sustituye, and the gerund is sustituyendo. The form sustituyo follows that pattern, not the plain stem plus -o.
- Wrong: Treating sustituir and reemplazar as identical in every context. — Right: Sustituir means to substitute, while reemplazar means to replace. — They overlap, but each has uses the other does not: sustituir fits sentences such as Sustituyo a un jugador lesionado, while reemplazar belongs in a different sentence. Check the meaning you want before choosing.
- Wrong: Yo soy sustituido el azúcar por miel. — Right: Yo he sustituido el azúcar por miel. — Spanish perfect tenses use haber, not ser: he sustituido, has sustituido, ha sustituido. Ser plus the participle makes a passive, not a perfect tense.
- Wrong: De niño, yo sustituí al profesor enfermo todos los días. — Right: De niño, yo sustituía al profesor enfermo todos los días. — For a repeated habit in the past, use the imperfect (sustituía), not the preterite. The preterite (sustituí) is for one finished action.
Quiz: test yourself
Ten questions on sustituir. Choose the right form, then check the answer key below.
Complete the sentence: Yo ___ a un jugador lesionado. (present tense) A. sustituyo B. sustituyes C. sustituye D. sustituimos
Complete the sentence: Ayer, él ___ el azúcar por miel. (preterite) A. sustituí B. sustituiste C. sustituimos D. sustituyó
Complete the sentence: Antes, nosotros ___ al profesor enfermo. (imperfect) A. sustituías B. sustituyo C. sustituíamos D. sustituía
Complete the sentence: Mañana, tú ___ una pieza rota del coche. (future) A. sustituiremos B. sustituirás C. sustituiré D. sustituirá
Complete the sentence: Yo ___ a un jugador lesionado si pudiera. (conditional) A. sustituiría B. sustituirías C. sustituiríamos D. sustituyo
Complete the sentence: Espero que él ___ el azúcar por miel. (present subjunctive) A. sustituyas B. sustituyamos C. sustituyo D. sustituya
Complete the sentence: Si yo ___ al profesor enfermo, todo cambiaría. (imperfect subjunctive, -ra form) A. sustituyéramos B. sustituyo C. sustituyera D. sustituyeras
Complete the sentence: Nosotros ___ una pieza rota del coche. (present perfect) A. ha sustituido B. hemos sustituido C. he sustituido D. has sustituido
Complete the command: ¡___ a un jugador lesionado! (affirmative imperative, tú) A. sustituye B. sustituya C. sustituyamos D. sustituid
Which is the gerund of sustituir, used with estar for the progressive? A. sustituido B. sustituyo C. sustituí D. sustituyendo
Answer key
- sustituyo — The yo present tense of sustituir is sustituyo.
- sustituyó — The él/ella/Ud. preterite of sustituir is sustituyó.
- sustituíamos — The nosotros/as imperfect of sustituir is sustituíamos.
- sustituirás — The tú future of sustituir is sustituirás.
- sustituiría — The yo conditional of sustituir is sustituiría.
- sustituya — The él/ella/Ud. present subjunctive of sustituir is sustituya.
- sustituyera — The yo imperfect subjunctive, -ra form of sustituir is sustituyera.
- hemos sustituido — The nosotros/as present perfect of sustituir is hemos sustituido.
- sustituye — The affirmative tú imperative of sustituir is sustituye.
- sustituyendo — The gerund of sustituir is sustituyendo: estoy sustituyendo. The participle sustituido is used with haber instead.
Frequently asked questions
What does sustituir mean in English?
Sustituir means to substitute. It is used in everyday situations such as Sustituyo a un jugador lesionado. The exact English wording depends on the context, but the core meaning stays the same across the tenses.
Is sustituir regular or irregular?
Sustituir is a spelling-change verb: it is a -uir verb: the stem vowel i becomes y before a vowel ending, so the present is sustituyo and sustituye, and the gerund is sustituyendo. The endings are regular, so once you know the pattern you can produce every form on this page, including sustituyo in the present and sustituí in the preterite.
What is the difference between sustituir and reemplazar?
Sustituir means to substitute, while reemplazar means to replace. They are easy to confuse because they appear in similar situations, but they are not interchangeable: use sustituir when you mean to substitute, as in Sustituyo a un jugador lesionado, and use reemplazar for to replace. When in doubt, check the object of the sentence — it usually shows which verb fits.
How do I say “I substitute” in the past?
It depends on the kind of past. For one finished action, use the preterite: yo sustituí el azúcar por miel. For a repeated habit or background in the past, use the imperfect: yo sustituía al profesor enfermo. For something that has just happened, use the present perfect: yo he sustituido el azúcar por miel.
How do I practise sustituir?
Start with the present tense table, then drill the preterite and the imperfect, since those two past tenses cause the most mistakes. Try the sustituir examples and quiz page for more sentences, and use the Spanish Verb Quiz to test the forms under pressure.
Related links
- Sustituir in the present tense — the full present-tense table for sustituir.
- Sustituir examples and quiz — more example sentences and practice for sustituir.
- Spanish verbs — the Spanish hub, with every verb and tense guide.
- Complete list of Spanish irregular verbs — where this verb's pattern is listed.
- Surgir conjugation — another -ir verb to compare with sustituir.
- Transmitir conjugation — another -ir verb to compare with sustituir.
- Sumergir conjugation — another -ir verb to compare with sustituir.
- Spanish Verb Conjugator — conjugate any Spanish verb in every tense.
- Spanish Verb Quiz — test yourself on real conjugated forms.