Introduction
Learning how to use infinitives in Spanish is one of the most fundamental skills for beginner learners. An infinitive is the base form of a verb that hasn’t been conjugated, such as hablar (to speak), comer (to eat), or vivir (to live). Understanding how to use infinitives with action structures will open up countless possibilities for expressing ideas, desires, and intentions in Spanish. This guide walks you through the essential patterns and constructions that will help you use infinitives confidently in everyday conversations and written Spanish.
What is an Infinitive in Spanish?
An infinitive is the unconjugated form of a verb. In English, infinitives are usually preceded by the word to, as in to run, to read, or to dance. In Spanish, infinitives always end in one of three ways: -ar, -er, or -ir. These endings help determine how the verb will be conjugated when you use it in different tenses and with different subjects.
The three types of Spanish infinitives are:
-ar verbs: hablar (to speak), caminar (to walk), estudiar (to study)
-er verbs: comer (to eat), beber (to drink), aprender (to learn)
-ir verbs: vivir (to live), escribir (to write), partir (to leave)
Infinitives are incredibly useful because they allow you to express actions without worrying about conjugation. You can use them to talk about what you want to do, what you need to do, or what you plan to do.
Using Infinitives with Modal Verbs
One of the most common ways to use infinitives in Spanish is with modal verbs, which express necessity, ability, permission, or desire. Modal verbs are always followed by an infinitive, and they help you express what you need, can, want, or should do.
The Most Important Modal Verbs
Poder (can, to be able to) expresses ability or possibility:
Yo puedo hablar español. (I can speak Spanish.)
Ellos pueden comer pizza. (They can eat pizza.)
Nosotros podemos vivir en Madrid. (We can live in Madrid.)
Deber (should, must, to have to) expresses obligation or necessity:
Debes estudiar más. (You should study more.)
Ella debe terminar su tarea. (She must finish her homework.)
Todos debemos respetar las reglas. (We all must respect the rules.)
Querer (to want) expresses desire:
Quiero aprender italiano. (I want to learn Italian.)
Queremos viajar a Barcelona. (We want to travel to Barcelona.)
Ella quiere bailar en la fiesta. (She wants to dance at the party.)
Necesitar (to need) expresses necessity:
Necesito practicar más. (I need to practice more.)
El necesita trabajar mañana. (He needs to work tomorrow.)
Necesitamos comprar comida. (We need to buy food.)
The Pattern for Modal Verbs with Infinitives
When using modal verbs, the structure is always: conjugated modal verb + infinitive. The modal verb changes based on the subject, but the infinitive stays in its base form:
Yo quiero comer. (I want to eat.)
Tú quieres comer. (You want to eat.)
Él quiere comer. (He wants to eat.)
Nosotros queremos comer. (We want to eat.)
Ellos quieren comer. (They want to eat.)
Notice how querer changes to match the subject, but the infinitive comer always stays the same.
Common Prepositions Before Infinitives
Several Spanish prepositions are followed by infinitives, and understanding these combinations will help you express relationships between actions more precisely. A preposition is a word that shows the relationship between a noun (or pronoun) and other words in a sentence.
Para (in order to, for)
Use para when expressing purpose or intention:
Estudio para aprender. (I study in order to learn.)
Voy a la tienda para comprar leche. (I go to the store to buy milk.)
Trabajo duro para tener éxito. (I work hard to have success.)
Por (for, because of)
Use por to express reason or cause:
Me gusta caminar por ejercitar mi cuerpo. (I like to walk for exercising my body.)
Estudiamos por mejorar nuestras notas. (We study because of improving our grades.)
Juego fútbol por divertirme. (I play football for having fun.)
Antes de (before) and Después de (after)
Use these prepositions to show temporal relationships:
Antes de dormir, leo un libro. (Before sleeping, I read a book.)
Después de trabajar, voy al gimnasio. (After working, I go to the gym.)
Antes de viajar, necesito comprar un pasaporte. (Before traveling, I need to buy a passport.)
Sin (without) and Con (with)
These prepositions show accompaniment or lack thereof:
No puedo estudiar sin escuchar música. (I cannot study without listening to music.)
Con practicar todos los días, mejorarás tu español. (By practicing every day, you will improve your Spanish.)
Salí sin decir adiós. (I left without saying goodbye.)
The Gerund as an Alternative to Infinitives
In Spanish, there’s another form similar to the infinitive called the gerund. The gerund is formed by adding -ando to -ar verbs and -iendo to -er and -ir verbs. It represents an action in progress or continuous action.
hablar becomes hablando (speaking)
comer becomes comiendo (eating)
vivir becomes viviendo (living)
The gerund is often used with the verb estar to create the present progressive tense:
Estoy estudiando español. (I am studying Spanish.)
Ella está cocinando la cena. (She is cooking dinner.)
Nosotros estamos corriendo en el parque. (We are running in the park.)
However, infinitives are more commonly used after modal verbs and prepositions, while gerunds are used with estar and other continuous constructions.
Reflexive Infinitives
Some infinitives are reflexive, meaning they include the reflexive pronoun se attached to the end of the verb. Reflexive verbs are actions that the subject performs on themselves. Common examples include levantarse (to get up), acostarse (to lie down), and divertirse (to have fun).
When using reflexive infinitives with modal verbs, the reflexive pronoun can either stay attached to the infinitive or move before the conjugated verb:
Quiero levantarme temprano. or Me quiero levantar temprano. (I want to get up early.)
Necesitas acostarte ahora. or Te necesitas acostar ahora. (You need to lie down now.)
Podemos divertirnos en la playa. or Nos podemos divertir en la playa. (We can have fun at the beach.)
Both structures are correct, though the first option (with the pronoun attached to the infinitive) is slightly more common in formal writing.
Practice Sentences and Examples
To solidify your understanding, here are some complete example sentences using infinitives in action structures:
Tengo que terminar mi proyecto antes de las cinco. (I have to finish my project before five o’clock.)
Prefiero salir con mis amigos después de trabajar. (I prefer to go out with my friends after working.)
Ella desea viajar sin gastar mucho dinero. (She wishes to travel without spending much money.)
Podemos intentar aprender nuevas palabras cada día. (We can try to learn new words every day.)
Necesito practicar para mejorar mi pronunciación. (I need to practice in order to improve my pronunciation.)
Ellos siguen queriendo jugar aunque están cansados. (They keep wanting to play even though they are tired.)
Notice how in each sentence, the infinitive expresses the action being performed, while the other elements show the time, purpose, or relationship to that action.
Tips for Learning Infinitive Structures
As a beginner learner, focus on mastering a few key modal verbs and prepositions before trying to learn every possible combination. Start with poder, querer, deber, and necesitar, and practice them with simple infinitives until they feel natural. Create flashcards with common infinitive phrases like quiero hablar, puedo comer, and necesito estudiar. Use these phrases in conversation and writing as much as possible. The more you practice, the more automatic these structures will become.
Conclusion
Infinitives are the foundation for building more complex Spanish sentences and expressing your intentions, desires, and obligations. By mastering modal verbs like poder, querer, deber, and necesitar, and understanding how prepositions combine with infinitives, you’ll have the tools to communicate effectively in Spanish. Remember that the key pattern is always: conjugated verb plus infinitive. Start with simple sentences, practice regularly, and gradually work toward more complex structures. With consistent effort and practice, using infinitives in action structures will become second nature, and you’ll find yourself expressing ideas in Spanish with increasing confidence and fluency.
