Indefinite Articles

01

Singular Forms: A or An

Use un before masculine singular nouns.

• Necesito un bolígrafo.

  I need a pen.

• Vivo en un piso pequeño.

  I live in a small flat.

Use una before feminine singular nouns.

• Es una idea fantástica.

  It is a fantastic idea.

• Quiero una manzana.

  I want an apple.

02

Plural Forms: Some

English often drops the article in the plural (e.g., "I have books") or uses "some." Spanish explicitly uses plural indefinite articles. Use unos for masculine plural nouns (or mixed groups) and unas for feminine plural nouns.

• He comprado unos zapatos negros.

  I bought some black shoes.

• Tengo unas entradas para el cine.

  I have some tickets for the cinema.

03

Feminine Nouns Starting with Stressed 'A'

There is a phonetic exception to the gender rule. If a feminine singular noun begins with a stressed "a" or "ha" sound, use the masculine article un instead of una. This prevents the two "a" sounds from blending together.

However, the noun remains feminine. If you add an adjective, it must still take the feminine form.

• El bosque tiene un área protegida.

  The forest has a protected area.

• Bebí un agua fría.

  I drank a cold water.

Note that in the plural, this rule does not apply because the "s" in unas separates the sounds.

• Bebí unas aguas frías.

  I drank some cold waters.

04

Distinguishing "A" from "One"

The words un and una are also the words for the number "one." The meaning is usually clear from the context.

• Solo quiero un billete.

  I only want one ticket.

• Busco un hotel en el centro.

  I am looking for a hotel in the center.

05

Approximation with Numbers

When placed before a number, the plural forms unos and unas take on the meaning of "approximately" or "about."

• El castillo está a unos diez kilómetros.

  The castle is about ten kilometers away.

• Había unas cincuenta personas.

  There were approximately fifty people.

06

Omission with Professions

Unlike in English, you generally do not use the indefinite article when stating a profession, religion, or nationality after the verb ser.

• Mi padre es profesor.

  My father is a teacher.

However, if you add an adjective to describe the noun, the article is required again.

• Mi padre es un profesor excelente.

  My father is an excellent teacher.