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Spanish Indefinite Pronouns: Algo, Alguien, Nadie and Nada

Learn how Spanish refers to unspecified people, things, quantities and groups. This guide explains algo, alguien, nada, nadie, alguno, ninguno, cualquiera and related forms, including personal a, agreement and Spanish negative sentence structure.

Open pronoun table Practice examples
Core distinction: use alguien and nadie for people; use algo and nada for things, ideas or unspecified information.
Spanish indefinite pronouns algo, alguien, nada, nadie, alguno, ninguno and cualquiera
Indefinite pronouns identify someone, something, nobody, nothing or an unspecified member of a group.

Definition

What are Spanish indefinite pronouns?

Indefinite pronouns refer to people, things, quantities or groups without identifying them precisely. They replace a noun or refer to something that remains unknown, general or unspecified.

Unspecified thing

Necesito algo.
I need something.

Unspecified person

Alguien llama.
Someone is calling.

Negative reference

No veo nada.
I do not see anything.

Some indefinite forms are always pronouns, while others can also function as determiners before a noun.

Pronoun table

Spanish indefinite pronouns at a glance

Pronoun Main meaning Spanish example English meaning Grammar note
algo something Necesito algo. I need something. Invariable; refers to things, ideas or information.
nada nothing; anything after negation No veo nada. I do not see anything. Invariable negative form.
alguien someone; anyone in questions Alguien llama. Someone is calling. Invariable; refers to people.
nadie nobody; anybody after negation No conozco a nadie. I do not know anyone. Invariable; refers to people.
alguno / alguna one, some, any ¿Tienes alguno? Do you have one or any? Agrees with the understood noun.
algunos / algunas some, some of them Algunos llegaron tarde. Some arrived late. Plural forms.
ninguno / ninguna none, not one No tengo ninguno. I do not have any. Negative counterpart of alguno.
cualquiera anyone, any one Cualquiera puede hacerlo. Anyone can do it. Unrestricted or unspecified choice.
todo everything Todo está listo. Everything is ready. Neutral singular reference.
todos / todas everyone, all of them Todos llegaron. Everyone arrived. Agrees with the group.
otro / otra another one Quiero otro. I want another one. Agrees with the noun replaced.
varios / varias several Varias respondieron. Several answered. Plural reference.
Memory line: algo = something · alguien = someone · nada = nothing · nadie = nobody

Core pairs

Algo and nada vs alguien and nadie

Affirmative thing

Algo

Refers to an unspecified thing, idea or piece of information.

Quiero algo.
I want something.

Affirmative person

Alguien

Refers to an unspecified or unknown person.

Alguien está en la puerta.
Someone is at the door.

Negative forms

Nada and nadie

Use nada for things and nadie for people.

No veo nada.
No veo a nadie.

Reference Affirmative or open form Negative form Examples
Thing, idea or information algo nada ¿Necesitas algo?
No necesito nada.
Person alguien nadie ¿Conoces a alguien?
No conozco a nadie.

Things and ideas

Algo and nada

Algo refers to an unspecified thing, idea, event or piece of information. Nada is the corresponding negative form.

Spanish sentence English meaning Use
Quiero algo. I want something. Unspecified thing.
¿Necesitas algo? Do you need anything? Open question.
No quiero nada. I do not want anything. Negative concord after the verb.
Nada funciona. Nothing works. Negative word before the verb.
Algo ha cambiado. Something has changed. Unspecified event or situation.

People

Alguien, nadie and the personal a

Alguien and nadie refer to people. They are grammatically singular and do not change according to gender.

Spanish sentence English meaning Grammar point
Alguien llama. Someone is calling. Alguien is the subject.
¿Conoces a alguien? Do you know anyone? Personal a before a person as object.
Nadie responde. Nobody answers. No additional no before the verb.
No conozco a nadie. I do not know anyone. Negative word follows the verb.
Busco a alguien que hable español. I am looking for someone who speaks Spanish. Unspecified person with a relative clause.
Use personal a for people:

Veo a alguien and No veo a nadie.
Do not use personal a with things: Veo algo and No veo nada.

One, some or none

Alguno, alguna, ninguno and ninguna

These pronouns replace a known or understood noun and agree with it in gender. The plural forms algunos and algunas mean “some” or “some of them”.

Form Reference Spanish example English meaning
alguno Masculine singular ¿Tienes alguno? Do you have one or any?
alguna Feminine singular Necesito alguna. I need one or some.
algunos Masculine or mixed plural Algunos llegaron tarde. Some arrived late.
algunas Feminine plural Algunas son difíciles. Some are difficult.
ninguno Masculine singular or neutral group reference No tengo ninguno. I do not have any.
ninguna Feminine singular No necesito ninguna. I do not need any.
Pronoun forms: alguno and ninguno
Before a masculine singular noun: algún libro and ningún libro

Plural ningunos and ningunas exist, but they are much less common and occur mainly with nouns normally used in the plural or in emphatic contexts.

Unrestricted choice

Cualquiera and cualquier

Cualquiera means “anyone”, “any one” or “whichever one”. It expresses an unrestricted or non-specific choice.

Structure Spanish example English meaning
Pronoun as subject Cualquiera puede aprender. Anyone can learn.
Pronoun as object Elige cualquiera. Choose any one.
Pronoun with de Cualquiera de estos sirve. Any of these works.
Before a singular noun Cualquier opción sirve. Any option works.
Position changes the form:

Use cualquiera when it stands alone. Use cualquier before a singular noun: cualquier persona and cualquier problema.

Additional forms

Todo, otro, varios and uno as pronouns

Everything

Todo

Todo está bien.
Everything is fine.

Everyone

Todos and todas

Todos entienden.
Everyone understands.

Another one

Otro and otra

Quiero otro.
I want another one.

Several

Varios and varias

Varias llegaron tarde.
Several arrived late.

One in general

Uno and una

Uno nunca sabe.
You never know.

One of a group

Uno de

Uno de ellos llamó.
One of them called.

Spanish negation

Negative concord: no veo nada

Spanish commonly uses more than one negative element in the same clause. This pattern is called negative concord. The negative words reinforce the same negation rather than cancelling each other.

Negative word before the verb Negative word after the verb English meaning
Nadie responde. No responde nadie. Nobody answers.
Nada funciona. No funciona nada. Nothing works.
Ninguno sirve. No sirve ninguno. None of them works.
Nadie lo sabe. No lo sabe nadie. Nobody knows it.
Position rule:
negative word before the verb: Nadie viene
negative word after the verb: No viene nadie

Study the complete system on the Spanish Negation page.

Grammar function

Indefinite pronouns vs indefinite determiners

A pronoun replaces a noun. A determiner appears before a noun and introduces it.

Pronoun use Determiner use Difference
Necesito alguno. Necesito algún libro. Alguno replaces the noun; algún introduces it.
No tengo ninguno. No tengo ningún problema. Ninguno stands alone; ningún appears before a noun.
Cualquiera sirve. Cualquier opción sirve. Cualquiera stands alone; cualquier introduces a noun.
Quiero otro. Quiero otro café. Otro can replace or accompany a noun.
Todos llegaron. Todos los estudiantes llegaron. The noun is understood in the pronoun structure.

Continue with: Spanish Indefinite Determiners .

Adjective patterns

Algo and nada with adjectives

When algo or nada refers to an unspecified thing, a following adjective normally appears in the masculine singular form.

Structure Spanish example English meaning
Something + adjective Quiero algo dulce. I want something sweet.
Something + adjective Pasó algo extraño. Something strange happened.
Nothing + adjective No ocurrió nada grave. Nothing serious happened.
Nothing + adjective No hay nada nuevo. There is nothing new.
Do not confuse two different uses of algo:

Quiero algo dulce means “I want something sweet”.
Es algo difícil can mean “It is somewhat difficult”. In the second sentence, algo expresses degree.

Mini practice

Practice Spanish indefinite pronouns

Complete each exercise before opening the answer.

Exercise 1: person or thing?

  1. Necesito ___. — something
  2. ___ llama. — someone
  3. No veo ___. — anything
  4. No conozco a ___. — anyone
Show answers

1. Necesito algo.
2. Alguien llama.
3. No veo nada.
4. No conozco a nadie.

Exercise 2: pronoun or determiner?

  1. Necesito ___ libro.
  2. ¿Tienes ___?
  3. No tengo ___ problema.
  4. No tengo ___.
Show answers

1. Necesito algún libro.
2. ¿Tienes alguno?
3. No tengo ningún problema.
4. No tengo ninguno.

Exercise 3: correct the negation

  1. Veo nada.
  2. Conozco a nadie.
  3. No nadie viene.
  4. No funciona ninguno.
Show answers

1. No veo nada.
2. No conozco a nadie.
3. Nadie viene.
4. No funciona ninguno. — already correct.

Common errors

Common mistakes with Spanish indefinite pronouns

  • Confusing people and things: use alguien and nadie for people; use algo and nada for things or ideas.
  • Forgetting personal a: say Veo a alguien and No veo a nadie.
  • Omitting no before a following negative word: say No veo nada, not Veo nada in a normal negative statement.
  • Adding no when the negative word comes first: say Nadie viene, not normally No nadie viene.
  • Using algún as a standalone pronoun: use alguno alone and algún before a masculine singular noun.
  • Using ningún as a standalone pronoun: use ninguno alone and ningún before a masculine singular noun.
  • Making alguien or nadie plural: both forms are invariable and normally take a singular verb.
  • Confusing cualquiera and cualquier: use cualquiera alone and cualquier before a singular noun.

Frequently asked questions

Questions about Spanish indefinite pronouns

What are Spanish indefinite pronouns?

They refer to unspecified people, things, quantities or groups. Examples include algo, alguien, nada, nadie, alguno, ninguno and cualquiera.

What is the difference between algo and alguien?

Algo refers to a thing, idea or piece of information. Alguien refers to a person.

What is the difference between nada and nadie?

Nada refers to things or ideas. Nadie refers to people.

Why does Spanish say no veo nada?

Spanish uses negative concord. When nada, nadie or ninguno appears after the verb, no normally appears before the verb.

What is the difference between alguno and algún?

Alguno can stand alone: ¿Tienes alguno? Algún appears before a masculine singular noun: ¿Tienes algún libro?

Do alguien and nadie use the personal a?

Yes, when they are direct objects referring to people: Veo a alguien and No veo a nadie.

Practice and support

Practise indefinite pronouns in complete sentences

These forms become easier when you practise the contrast between people and things, personal a, gender agreement and Spanish negative concord.

Grammar support

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