Making Words Match: Adjectives & Agreement

In Spanish, describing words do not stay the same the way they do in English. An adjective changes its ending to match the noun it describes. Once you learn this simple habit of matching, your Spanish will sound natural and your writing will look correct. Let's make the pieces fit together.

The core idea: adjectives agree with the noun

In English, an adjective never changes: we say a tall boy and a tall girl, one tall boy and two tall boys. The word "tall" stays exactly the same.

Spanish is different. An adjective must agree with its noun in two ways:

• Gender — masculine or feminine, to match the noun.
• Number — singular or plural, to match the noun.

So the single English word "tall" can become four different Spanish words, depending on who or what you are describing. Look at how alto (tall) shifts to fit the noun:

• el chico alto — the tall boy
• la chica alta — the tall girl
• los chicos altos — the tall boys
• las chicas altas — the tall girls

Notice that the article (el, la, los, las), the noun, and the adjective all match. Everything travels together. That teamwork is the heart of this lesson.

Four-form adjectives ending in -o

The most common pattern is the adjective that ends in -o. These have four forms. Take the ending off and add the right one:

• masculine singular: -o
• feminine singular: -a
• masculine plural: -os
• feminine plural: -as

Here is alto in all four forms, with a noun for each:

Many everyday adjectives follow this exact pattern: rojo (red), pequeño (small), bonito (pretty), nuevo (new), blanco (white). Learn one and you can do them all.

Adjectives ending in -e or a consonant

Good news: many adjectives are simpler. Adjectives that end in -e, and most that end in a consonant, use the same form for masculine and feminine. You only change them for the plural.

For example, inteligente (intelligent) stays the same for a boy or a girl:

Other adjectives in this group: interesante (interesting), verde (green), joven (young), difícil (difficult). For these you do not worry about masculine or feminine at all in the singular — just number.

One important exception: adjectives of nationality that end in a consonant do add -a for the feminine. So they behave more like the -o group:

Notice that the written accent disappears in the feminine: francés becomes francesa.

Making adjectives plural

The plural rule for adjectives is the same friendly rule you already know for nouns:

• Ends in a vowel → add -s.
• Ends in a consonant → add -es.

So "the blue houses" is las casas azules, and "the easy lessons" is las lecciones fáciles. Just remember the vowel-or-consonant test at the end of the word.

Where the adjective goes

In English the adjective comes first: a white house. In Spanish, descriptive adjectives usually come after the noun:

• una casa blanca — a white house
• un coche rojo — a red car
• una película interesante — an interesting film

A few very common adjectives go before the noun instead. Three of them shorten (this shortening is called apocope) when they sit right before a masculine singular noun:

Two things to notice. First, bueno and malo shorten only before a masculine singular noun; before a feminine noun they keep their full form: una buena amiga (a good female friend). Second, grande shortens to gran before any singular noun, masculine or feminine, and its meaning shifts to "great": una gran idea, un gran hombre.

• ⚠️ Common mistakes
  • Saying una casa blanco. The adjective must match the feminine noun: una casa blanca.
  • Putting the color first, English-style: una roja flor. Say una flor roja.
  • Forgetting to make the adjective plural: los coches rojo. It must also be plural: los coches rojos.
  • Leaving bueno full before a masculine noun: un bueno amigo. Shorten it: un buen amigo.

Ser + adjective to describe someone

To describe what someone or something is like, use the verb ser (to be) plus an adjective. The adjective still agrees with the subject:

• Ella es amable — She is kind.
• Él es alto — He is tall.
• Los niños son inteligentes — The children are intelligent.
• Las casas son grandes — The houses are big.

Here is a small bank of useful descriptive adjectives to practice with:

You are building a real, correct habit here: let the noun lead, and let the adjective follow its gender and number. It feels like extra work at first, but very soon the matching endings will come out automatically. Keep describing the world around you in Spanish, and every sentence you build makes the pattern stronger. ¡Muy bien!