The infinitive in Spanish : complete course

What Is the Infinitive in Spanish?

The infinitive in Spanish is the base form of a verb. It is the form you find in the dictionary. It does not change based on who is speaking or when the action happens.

In Spanish, all infinitives end in one of three ways: -ar, -er, or -ir. For example, hablar means ‘to speak’, comer means ‘to eat’, and vivir means ‘to live’.

Simple Examples to Get Started

Here are a few common Spanish infinitives you may already know:

• hablar — to speak
• comer — to eat
• vivir — to live
• beber — to drink
• escribir — to write
• trabajar — to work

Notice how each verb ends in -ar, -er, or -ir. This ending tells you it is still in its base form — no conjugation yet!

The Key Elements of the Infinitive in Spanish

Let us look at the main components of the Spanish infinitive. Understanding these parts will help you recognize and use infinitives with confidence.

The Three Verb Groups

Spanish infinitives are divided into three groups based on their ending. Each group follows its own conjugation pattern later on, but for now, just focus on recognizing them.

The Stem and the Ending

Every Spanish infinitive is made of two parts: the stem and the ending.

• habl-ar → stem: habl-, ending: -ar
• com-er → stem: com-, ending: -er
• viv-ir → stem: viv-, ending: -ir

The stem carries the meaning of the verb. The ending tells you which group it belongs to. When you conjugate a verb, you usually keep the stem and change the ending.

Using the Infinitive After Another Verb

In Spanish, the infinitive is often used directly after another conjugated verb. This is very common in everyday speech.

• Quiero comer. — I want to eat.
• Necesito hablar. — I need to speak.
• Me gusta bailar. — I like to dance.

In these sentences, the first verb is conjugated (quiero, necesito, gusta), and the second verb stays in the infinitive form.

Why the Infinitive in Spanish Matters

The infinitive is one of the first things you learn in Spanish — and for a good reason. It is everywhere! Here is why it is so important:

• It is the form listed in every dictionary. Knowing it helps you look up any verb.
• It is used after many common verbs like querer (to want), poder (to be able to), and deber (must).
• It helps you build sentences quickly, even before you know all the conjugation rules.
• It is a building block for other verb forms and tenses you will learn later.

Simply put, the infinitive is your starting point in Spanish. Master it, and everything else becomes easier.

Comparison With Other Languages

If you speak English or French, you already have a good idea of what an infinitive is. Let us compare the three languages:

In English, the infinitive is usually introduced by the word ‘to’: to eat, to work. In French and Spanish, the infinitive is shown by a specific verb ending. Spanish and French are quite similar here — both use verb endings to mark the infinitive. However, Spanish only has three possible endings (-ar, -er, -ir), while French has three as well (-er, -ir, -re), but with different sounds and patterns.

One key difference: in Spanish, you do NOT need a word like ‘to’ before the infinitive when it follows another verb. You simply place the two verbs together.

A Complete Example

Let us look at a short, simple dialogue that uses infinitives naturally:

• — ¿Qué quieres hacer hoy? — What do you want to do today?
• — Quiero comer y después descansar. — I want to eat and then rest.
• — ¿Y necesitas trabajar? — And do you need to work?
• — No, hoy no necesito trabajar. — No, today I do not need to work.

In this dialogue, hacer, comer, descansar, and trabajar are all infinitives. They follow conjugated verbs like quieres, quiero, and necesito. This structure is very natural in Spanish.

Key Points to Remember

• The Spanish infinitive is the base form of a verb — it is not conjugated.
• All infinitives end in -ar, -er, or -ir.
• Every infinitive has a stem (the meaning part) and an ending (the group marker).
• Infinitives are used after conjugated verbs like querer, poder, necesitar, and gustar.
• You do not need a word like ‘to’ before the infinitive in Spanish — just put the verbs together.
• Recognizing infinitives is your first step to understanding Spanish verbs.

Take your time with this concept. Once you feel comfortable recognizing and using infinitives, the rest of Spanish grammar will start to make much more sense. Keep practicing with simple sentences, and you will progress quickly!

Sources

• Real Academia Española. (2010). Nueva gramática de la lengua española. Espasa Libros.
• Bosque, I., & Demonte, V. (1999). Gramática descriptiva de la lengua española. Espasa Calpe.
• Butt, J., & Benjamin, C. (2011). A New Reference Grammar of Modern Spanish (5th ed.). Hodder Education.