Inklingo

How to Say "to base" in Spanish

The most common Spanish word for “to base” is “basar” — use 'basar' when you mean to use something as the foundation or underlying principle for an idea, argument, or work.

English → Spanish

basar

bah-SAHRbaˈsaɾ

verbB1
Use 'basar' when you mean to use something as the foundation or underlying principle for an idea, argument, or work.
A strong stone foundation being laid for a house.

Examples

Tienes que basar tus argumentos en hechos reales.

You have to base your arguments on real facts.

El arquitecto decidió basar el diseño en la luz natural.

The architect decided to base the design on natural light.

No puedes basar una relación únicamente en la apariencia.

You cannot base a relationship solely on appearance.

The 'EN' Rule

In Spanish, you almost always follow 'basar' with the word 'en' to say what you are basing something on.

Active vs. Passive

Use 'basar' when you are the one doing the basing, but use 'basarse' when you want to say something 'is based on' something else.

Wrong Preposition

Mistake: “Basar sobre hechos.”

Correction: Basar en hechos. Even though 'sobre' means 'on', Spanish logic uses 'en' (in) for foundations.

apoya

ah-POY-ahaˈpoʝa

verbB1
Use 'apoya' (from 'apoyar') when you mean to lean something physically against a support or to support an idea or person, rather than founding something on a principle.
A wooden ladder resting against a sturdy brick wall.

Examples

Él apoya la escalera en la pared.

He leans the ladder against the wall.

Apoya tu cabeza en mi hombro.

Rest your head on my shoulder.

Physical Leaning

When using this word for leaning, you often use the word 'en' (on/in) or 'contra' (against) to show where the object is placed.

base

BAH-sehˈba.se

verbB1
Use 'base' (from 'basar') when you mean to establish or found an argument, idea, or presentation on specific information or data.
A cartoon character carefully placing a small, colorful structure onto a massive, unmoving stone cube, symbolizing founding an idea on a fact.

Examples

Espero que ella base su presentación en datos reales.

I hope she bases her presentation on real data.

¡Base sus conclusiones en la evidencia!

Base your conclusions on the evidence!

This is a Form of the Verb 'basar'

The word 'base' is a command form ('Usted base...') and also a special form used for wishes or doubts ('Espero que él base...'). The main, dictionary form of the verb is 'basar'.

Almost Always Used with 'en'

When you use this verb, you almost always follow it with the word 'en' to say what something is based on. For example, 'Baso mi opinión en los hechos' (I base my opinion on the facts).

fundar

foon-DAHRfunˈdaɾ

verbB2
Use 'fundar' when you are emphasizing the act of establishing or grounding an argument or accusation firmly on evidence or facts, often with a more formal or serious tone.
A small wooden house sitting on a very thick and solid grey stone foundation.

Examples

No puedes fundar tu acusación solo en rumores.

You cannot base your accusation solely on rumors.

Su teoría se funda en años de investigación científica.

His theory is based on years of scientific research.

El juez debe fundar su sentencia en la ley.

The judge must ground his sentence in the law.

Using 'En'

When you want to say you are basing an idea 'on' something, always use the word 'en'. For example: 'Se funda en la verdad' (It is based on the truth).

Reflexive Use

You will often see this as 'fundarse' (to be based). It’s a very common way to describe theories or legal decisions in the passive voice.

Wrong Preposition

Mistake: “Fundo mi idea sobre la experiencia.”

Correction: Fundo mi idea en la experiencia. (Use 'en' instead of 'sobre' when talking about foundations for arguments.)

Basar vs. Apoyar

Learners often confuse 'basar' and 'apoyar'. Remember that 'basar' is about using something as a foundation for an idea or work, like basing an argument on facts. 'Apoyar' is typically about physical support (leaning something) or providing emotional/financial support, not about the conceptual foundation of an argument.

Related Translations

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