The Subjunctive in Relative Clauses

A relative clause is the bit that describes a noun - the man who lives next door, a house that has a garden, someone who can help. In Spanish the verb inside that clause can be either indicative or subjunctive, and no trigger word decides it. The choice is the speaker's, and it hangs on a single question: is the thing being described a specific, real thing you have in mind, or an open description of something wanted, sought, or not there at all?

• Conozco a alguien que habla ruso. (I know someone who speaks Russian.) - a real, particular person; indicative.
• Busco a alguien que hable ruso. (I'm looking for someone who speaks Russian.) - anyone who fits, no one in particular; subjunctive.

That is the whole idea. This page assumes you can already form the present subjunctive; the work here is learning to feel where the line falls.

The rule: known antecedent = indicative, unknown = subjunctive

The noun a relative clause hangs off is its antecedent. Decide what you know about it:

• Definite and known - you have a specific thing in mind, and you are asserting it exists and has this quality. Use the indicative.
• Indefinite or unknown - the antecedent is a description of something you want, need, seek or are asking about, and whose existence or identity is unsettled. Use the subjunctive.

Tengo un coche que gasta poco asserts a real car I own that is economical. Quiero un coche que gaste poco describes a car I do not yet have and might not find. Same noun, same relative pronoun, opposite mood - and the meaning is carried entirely by that switch.

The wish list: wanting, seeking, needing

The commonest home for this subjunctive is the search or the requirement - the mental want-ad. The verbs buscar, querer, necesitar, preferir naturally set up an antecedent that is a description, not a known thing.

• Busco un piso que tenga balcón y esté cerca del metro. (I'm looking for a flat that has a balcony and is near the underground.)
• Necesitamos una persona que sepa programar. (We need a person who knows how to program.)
• Quiero comprar algo que no cueste mucho. (I want to buy something that doesn't cost much.)
• ¿Conoces un restaurante que abra los lunes? (Do you know a restaurant that opens on Mondays?)

None of these commits to a particular flat, person, thing or restaurant existing. Contrast the moment the thing becomes real and known:

• Encontré un piso que tiene balcón. (I found a flat that has a balcony.) - it exists, I found it, indicative.
• Trabaja con una persona que sabe programar. (He works with a person who knows how to program.) - a real colleague, indicative.

The non-existent antecedent: no hay nadie que...

When the main clause denies that the antecedent exists at all, the relative clause is always subjunctive - you cannot use the indicative to describe something you are saying is not there. This is the territory of no hay, nadie, nada, ningún.

• No hay nadie que lo sepa. (There's nobody who knows it.)
• No hay nada que me guste en esta carta. (There's nothing I like on this menu.)
• No conozco a ningún médico que trabaje los domingos. (I don't know any doctor who works on Sundays.)
• No existe un remedio que lo cure todo. (There's no cure-all.)

The negation empties the antecedent of existence, and an empty antecedent can only be described hypothetically, so: subjunctive, every time.

The questioned antecedent: ¿hay alguien que...?

A question about whether the antecedent exists sits on the same fence - the speaker does not yet know if such a thing is there, so the clause is subjunctive.

• ¿Hay alguien que hable inglés aquí? (Is there anyone here who speaks English?)
• ¿Conoces a alguien que pueda arreglarlo? (Do you know anyone who can fix it?)
• ¿Tienes algún libro que trate de esto? (Do you have any book that deals with this?)

If the answer turns out yes and the person is then identified, a reply about that known person swings back to the indicative: Sí, María habla inglés.

The disappearing personal a

Spanish normally puts the personal a before a specific human direct object - veo a Marta, busco a mi hermano. But when the human antecedent is indefinite and unidentified, that a tends to drop, and its presence or absence becomes a quiet signal of exactly the known-unknown distinction this page is about.

• Busco un empleado que sepa alemán. (I'm looking for an employee who knows German.) - no particular person, no a, subjunctive.
• Busco al empleado que sabe alemán. (I'm looking for the employee who knows German.) - a specific known employee, a kept, indicative.

The exception: alguien, nadie, alguno, ninguno keep the personal a even when indefinite, because they are grammatically personal pronouns.

• Busco a alguien que sepa alemán. (with a, subjunctive - indefinite but still takes a.)
• No veo a nadie que pueda ayudar. (with a, subjunctive.)

So: drop the a before an indefinite common noun, keep it before those four pronouns.

The superlative and "the only" antecedent

A relative clause after a superlative or after el único / el primero / el último often takes the subjunctive, softening the strong claim into something more like an opinion or a limit of the speaker's knowledge.

• Es la mejor película que haya visto nunca. (It's the best film I have ever seen.)
• Eres la única persona que me entienda. (You're the only person who understands me.)
• Fue el primer coche que tuviéramos. (It was the first car we ever had.)

The plain indicative is also correct here and asserts the fact more flatly (la mejor película que he visto); the subjunctive adds a shade of "as far as I know". Both are heard.

haga lo que haga: the concessive doubling

Reduplicating a subjunctive verb around a relative word builds the "whatever / wherever / however" concessive - the pattern that says the outcome holds no matter what.

• Haga lo que haga, no le hacen caso. (Whatever he does, they ignore him.)
• Vayas donde vayas, te encontraré. (Wherever you go, I'll find you.)
• Sea quien sea, que espere. (Whoever it is, let them wait.)
• Cueste lo que cueste, lo terminaremos. (Whatever it costs, we'll finish it.)

Both verbs are subjunctive, and the antecedent is maximally open - it could be anything - which is why this is the natural extreme of the whole unknown-antecedent idea.

Worked examples

• Necesito un diccionario que tenga ejemplos. (I need a dictionary that has examples.) - wanted, unknown, subjunctive.
• Este es el diccionario que tiene ejemplos. (This is the dictionary that has examples.) - specific, known, indicative.
• No hay nadie que cocine como mi abuela. (There's nobody who cooks like my grandmother.) - non-existent antecedent.
• ¿Hay algún tren que salga antes de las ocho? (Is there any train that leaves before eight?) - questioned antecedent.
• Busco a alguien que haya vivido en Japón. (I'm looking for someone who has lived in Japan.) - indefinite person, a kept, and note the perfect subjunctive haya vivido.
• Contrataron al ingeniero que había diseñado el puente. (They hired the engineer who had designed the bridge.) - specific known person, indicative.

Common mistakes English speakers make

Using the indicative for a wanted thing. English draws no distinction - "I'm looking for a flat that has a balcony" uses the plain present either way. Spanish does not: if the flat is not yet found, it is un piso que tenga balcón, subjunctive. Ask yourself whether the thing is real and identified; if not, switch to the subjunctive.

Using the subjunctive for a thing you have. The mirror error. Once you have found it, own it, or can point at it, the antecedent is known and the clause is indicative: encontré un piso que tiene balcón, not "que tenga".

Keeping the personal a before an indefinite common noun. Busco a un empleado que sepa alemán over-marks it; when no specific person is meant, drop the a: busco un empleado que sepa alemán. But keep it before alguien / nadie.

Forgetting that no hay forces the subjunctive. "No hay nadie que sabe" is wrong; a denied antecedent can only be described hypothetically: no hay nadie que sepa.

Feel the antecedent first, choose the mood second. Known, real, in-hand - indicative. Wanted, sought, doubted, denied, questioned - subjunctive. That single decision is the whole of the relative-clause subjunctive.

See also

• The present subjunctive: forms - the paradigm the relative clause draws on.
• The subjunctive after doubt and denial - the same known-unknown instinct, triggered by a verb instead of an antecedent.
• The personal a - why the a comes and goes in front of the person being sought.
• The Spanish grammar cheatsheet has the known-versus-unknown antecedent test on one card.