Noun-Adjective Agreement

Many adjectives inflected for number and gender

red bed
La cama es roja. (The bed is red.). Prayitno/Creative Commons.

Noun-adjective agreement is one of the fundamental rules of Spanish grammar: Adjectives must agree with the nouns they refer to in both number and gender.

Agreement: a Basic Rules of Spanish Grammar

In other words, singular nouns are accompanied by singular adjectives, and plural nouns are accompanied by plural adjectives. Masculine nouns are described by masculine adjectives, and feminine nouns are described by feminine adjectives.

The same rule applies to definite articles (the equivalent of "the") and indefinite articles (a class of words that in English include "a," "an" and "any"), both of which sometimes are considered types of adjectives.

How To Modify Adjectives for Number and Gender

Generally, the "normal" form of adjectives, the form you will find listed in dictionaries, is singular and masculine. To make the adjective plural, follow one of these steps:

  • If it ends in an unstressed vowel, add -s. Examples: verde ("green," singular), verdes ("green," plural). El árbol es verde, the tree is green. Los árboles son verdes, the trees are green.
  • If it ends in a z, change the z to a c and add -es. Example: feliz ("happy," singular), felices ("happy," plural). Soy feliz, I'm a happy person; somos felices, we are happy people.
  • If it ends in another consonant or a stressed vowel, add -es. Example: difícil ("difficult," singular), difíciles ("difficult," plural). La tarea es difícil, the task is difficult; las tareas son difíciles, the tasks are difficult.
  • Note that in some cases it is necessary to add an accent mark to maintain the stress on the correct syllable or delete one when it's no longer necessary to indicate stress.

Making a masculine adjective feminine is even easier. Just follow these steps:

  • If the singular masculine adjective ends in an -o, change it to an -a. Example: pequeño ("small," masculine singular), pequeña ("small," feminine singular). El gato es pequeño, the cat is small; los gatos son pequeños, the cats are small; la chica es pequeña, the girl is small; las chicas son pequeñas, the girls are small.
  • If the singular masculine adjective ends in any other letter, the feminine form is the same. El autobús es grande, the bus is big; la casa es grande, the house is big.

Adjectives can come before or after nouns, or they can be used with verbs such as ser ("to be") to describe nouns. But (except for invariable adjectives) they will always match the nouns they describe in both number and gender.

Invariable Adjectives

There are a few adjectives, known as invariable adjectives, that don't change in form. Most of them are either uncommon colors or words of foreign origin. An example is web as in la página web (the web page) and las páginas web (the web pages). Sometimes a noun can be used as an invariable adjective, but this practice is much less common in Spanish than in English. As a beginner you will seldom have the need to use invariable adjectives, but you should be aware that they exist so they don't confuse you when you see them.

Sample Sentences Demonstrating Noun-Adjective Agreement

Las familias felices se divierten en la playa rocosa. (The happy families are enjoying themselves on the rocky beach.) Felices is plural because familias is plural. The feminine form rocosa is used because playa is feminine. La and las are feminine definite articles.

El hombre feliz va a ascender al pico rocoso. (The happy man is going to climb to the rocky summit.) The singular feliz is used because there is only one man. The masculine rocoso is used because pico is masculine. El is a masculine definite article. Al is a contracted form of a plus el.

Ha sido un día largo entre muchas semanas largas. (It has been a long day among many long weeks.) The singular masculine largo is used with día because día is masculine and there is one of them, but the plural feminine largas is used with semanas because semana is feminine and there are more than one. Un and muchas are masculine and feminine indefinite articles, respectively.

Un taco es una preparación mexicana que en su forma estándar consiste en una tortilla que contiene algún alimento dentro. (A taco is a Mexican preparation that in its standard form consists of a tortilla the contains some food inside. Estándar is an invariable adjective — the same word would have been used with plural or masculine nouns.)