Infinitives are the basic form of a verb, which means they are not conjugated. In Spanish, they are verbs that end in either -ar, -er, and -ir. According to these endings, infinitives are classified into three classes or conjugations:
|First conjugation||caminar||to walk|
|Second conjugation||comer||to eat|
|Third conjugation||vivir||to live|
Infinitives can be used three ways: as a subject, after a conjugated verb, or after a preposition.
|As a subject||Vivir aquí es un privilegio.||Living here is a privilege.|
|After a verb||Olvidé devolver el libro.||I forgot to return the book.|
|After a preposition||Revísalo antes de dormir.||Double-check before going to bed.|
When we compare the previous examples with their translations, it’s noticeable how English often uses gerunds (verbs ending in “-ing”) in the contexts in which Spanish prefers infinitives.
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Table of Contents
When to use infinitives in Spanish?
In most cases, infinitives in Spanish function very similarly to infinitives in English; however, unlike English, Spanish infinitives can also function as nouns, for example, the subject of a verb. The equivalent of this verbal noun in English is a gerund – verbs ending in “-ing.” As you can see, there are some key differences between the use of the infinitive in Spanish and English. Let’s explore them.
Infinitive as a subject of the verb
In Spanish, infinitives can be used as the subject of a verb. When infinitives are used as subjects, they usually appear before the verb and can optionally be preceded by the definite article el (the). Notice that in English, when a verb is used as a subject, it uses a gerund – a verb ending in “-ing.”
(El) Hacer ejercicio es bueno para la salud.
Working out is good for your health.
There are two other uses of infinitives as subjects that are different from English.
- The verb gustar (to like) and similar verbs that require indirect object pronouns are followed by their subject. When the subject of these verbs is a verb, it must be an infinitive. Notice that in English you would use an “-ing” verb or an infinitive with “to,” but in Spanish a gerund is not possible after these types of verbs.
Me gusta nadar por las mañanas.
I like swimming/to swim in the mornings.
Le encanta leer novelas románticas.
He loves reading/to read romance books.
- Infinitives are also used after impersonal constructions with ser as in, es + adjective + infinitive and es + article/possessive + noun + ser (infinitive) + adjective:
Es necesario estudiar.
It’s necessary to study.
Es un placer ayudar.
It’s a pleasure to help.
Es mi obligación ser puntual.
It’s my obligation to be punctual.
Ayudar es un placer.
Helping is a pleasure.
Infinitive after a conjugated verb
Similar to English, infinitives are used after a conjugated verb. For example, after a modal verb or as complements of a verb.
I want to start.
Luis doesn’t know how to ski.
There are verbs in Spanish that require a particular preposition before adding an infinitive. To know more about these verbs, keep reading!
⤷TIP Notice that in English some conjugated verbs are followed by an infinitive with “to,” while others are followed by an infinitive without “to.” In Spanish, you need the infinitive in either case:.
Debo acabar antes de la medianoche.
I must finish before midnight.
Necesitas estudiar más.
You need to study more.
In English there are certain verbs, like “avoid,” “enjoy,” and “imagine,” that must be followed by an “-ing” verb, whereas in Spanish you must use an infinitive:
Manuel disfruta hablar en público.
Manuel enjoys speaking in public.
Check out a complete list of Spanish verbs followed by an infinitive here.
In Spanish, many verbs can be followed by a gerund, but be mindful that the function of the gerund is to describe how an action is done, for example:
Entró corriendo a la habitación.
She ran into the room. Literal: She entered the room running.
In this case the gerund answers the question “how (did she enter the room)?” Answer = corriendo (running).
For more on how to use gerunds in Spanish and other verbs that can precede the gerund, check out our post!
Infinitive after a preposition
In Spanish, when you use a verb after a preposition, you always need it to be in the infinitive form. Notice that in English you use an “-ing” verb.
Lo hice sin pensar.
I did it without thinking.
Verbs that require a preposition, such as venir a (to come to), llegar a (to come to), andar/caminar a (to walk to), correr a (to run to), salir a (to leave to), are always followed by an infinitive.
I came to buy a pair of shoes.
For more Spanish verbs followed by a preposition, click the link!
Certain verbs that denote beginning and end have two forms 1) followed by preposition por + infinitive, and 2) followed by a gerund. Although they are mostly interchangeable, there is a slight difference. Using por indicates that the action of the infinitive verb is the first or last in a series of successive actions. Using the gerund, instead, can perform this same function, but it can also simply describe the way that something is started or finished.
|Empezar por (to start by) + infinitive|
Empecé por limpiar el patio.
I started by cleaning the patio.
⤷implies that it was the first step of a series of actions related to cleaning
|Empezar (to start) + gerund|
Empecé limpiando el patio.
I started by cleaning the patio.
⤷implies something (e.g. my morning) started with me cleaning the patio
|Acabar por (to end up) + infinitive|
Acabé por aceptar la decisión.
I ended up accepting the decision.
⤷implies that it was the last step of a series of actions leading up to the decision.
|Acabar + gerund|
Acabé aceptando la decisión.
I ended up accepting the decision.
⤷implies something was ended with the acceptance of a decision (e.g. a meeting)
- An infinitive is used after expressions including a preposition such as fácil de (easy to), difícil de (difficult to), posible de (possible to), and imposible de (impossible to):
Este libro es imposible de terminar.
This book is impossible to finish.
- We use an infinitive after al (a +el) for actions that occur at the same time as the main verb. The English equivalent of this construction would be “upon + -ing verb”:
Al entrar, dijo hola.
Upon entering, he said hello.
- The use of infinitives after a preposition contrasts with use of the subjunctive after certain prepositions followed by que (antes de que (before), después de que (after), para que (in order to), etc). An infinitive without que is used when the subject is the same in both parts of the sentence, whereas the subjunctive is used after que when the subjects are different:
Lo hice antes de salir.
I did it before leaving.
Lo hice antes de que llegaras.
I did it before you arrived.
- We use an infinitive after expressions with hay que (to have to) or tener que (to have to) (including hay/tener algo que (something to) /nada que (nothing to) /poco que (little to)):
Hay que escoger el tipo de tela que quieres para el traje.
We have to choose the type of fabric you want for the suit.
Tengo que terminar antes de mañana.
I have to finish before tomorrow.
No tienes nada que perder.
You have nothing to lose.
Want to know more about these expressions? Check out “How to express obligation in Spanish?”
- An infinitive is equivalent to a command or a general statement in signs, posters, questions, and ads:
¿Por qué pagar más?
Why pay more?
How to form and use the perfect infinitive in Spanish?
The perfect infinitive is formed using the infinitive of the auxiliary haber (to have) followed by the past participle of a verb. It is used together with another verb to express an action that occurred before the action of the main verb. In order to use it, both actions must have the same subject. Perfect infinitives are used in the same contexts as simple infinitives (as the subject or after a conjugated verb and after a preposition) like in the following examples:
El haber estudiado todos los días me ayudó a pasar el examen.
Having studied every day helped me pass the exam.
Espero haber resuelto tus dudas.
I hope I have resolved your questions.
Salió sin haber terminado la tarea.
He left without having finished his homework.
⤷TIP You can use preposition de followed by the perfect infinitive to state a condition.
De no haber salido a tiempo, habríamos perdido el avión.
If we hadn’t left on time, we would have missed our flight.
Infinitives are the standard dictionary form of all verbs. They can end in either -ar, -er, or -ir. They can function like nouns, therefore, they can be the subject of a sentence. Infinitives are used more frequently in Spanish than in English:
- Verbs and expressions that require an infinitive in English also require an infinitive in Spanish.
- Almost all verbs that are followed by an “-ing” verb in English are followed by an infinitive in Spanish.
- Prepositions require a “-ing” verb in English, but they require an infinitive in Spanish.
Check out this chart with a summary of uses of the Spanish infinitive and examples.
The subject of a sentence is who/what performs the action.
María terminó el trabajo.
María finished the job.
The object of a preposition is the noun or pronoun that follows a preposition in a sentence.
Hablaré con ellos.
I will speak to them.
Impersonal constructions are sentences with an unidentified, or implied subject.
A modal verb is a verb that indicates possibility, ability, obligation, necessity, or permission:
He may come. (possibility)
She can run very fast. (ability)
He must be here at 9:00. (obligation)
You may not swim here. (permission)