Plural forms of nouns.How to change a noun to plural.

To form the plural of most Spanish nouns, look at the word's final letter.

• If a noun ends in an unstressed vowel, add -s.La casa es grande. Las casas son grandes. — The house is big. The houses are big.
• If a noun ends in a consonant, add -es.El animal duerme. Los animales duermen. — The animal is sleeping. The animals are sleeping.
• If a noun ends in -z, change the z to c and add -es.La luz está encendida. Las luces están encendidas. — The light is on. The lights are on.

Some endings require special attention. Nouns ending in unstressed -s or -x generally do not change in the plural, while nouns ending in a stressed vowel usually add -s.

• El lunes trabajo. Los lunes trabajo. — I work on Monday. I work on Mondays.
• El sofá es cómodo. Los sofás son cómodos. — The sofa is comfortable. The sofas are comfortable.

Different vowel and consonant endings follow these patterns.

Vowels

• Nouns ending in an unstressed -a, -e, or -o add -s.El perro corre. Los perros corren. — The dog runs. The dogs run.
• Nouns ending in a stressed -í or -ú commonly add -es; forms in -s are also used for some words.El rubí brilla. Los rubíes brillan. — The ruby shines. The rubies shine.El tabú es antiguo. Los tabúes son antiguos. — The taboo is old. The taboos are old.
• Nouns ending in a stressed -á, -é, or -ó normally add -s.El café está caliente. Los cafés están calientes. — The coffee is hot. The coffees are hot.

Consonants

• Most nouns ending in a consonant add -es.El reloj funciona. Los relojes funcionan. — The watch works. The watches work.La mujer sonríe. Las mujeres sonríen. — The woman smiles. The women smile.
• Nouns ending in -z change z to c before adding -es.El lápiz está en la mesa. Los lápices están en la mesa. — The pencil is on the table. The pencils are on the table.

When a noun ends in z, replace the z with c and add -es. The resulting plural spelling preserves the Spanish sound represented by c before e.

• El pez nada. Los peces nadan. — The fish swims. The fish swim.
• La voz es clara. Las voces son claras. — The voice is clear. The voices are clear.
• La luz está encendida. Las luces están encendidas. — The light is on. The lights are on.

Compound nouns do not all form their plurals in the same way. Many compounds made from a verb and a noun are invariable: the form remains the same in the plural, and the article or another determiner shows the number.

• El lavaplatos está lleno. Los lavaplatos están llenos. — The dishwasher is full. The dishwashers are full.
• El paraguas está roto. Los paraguas están rotos. — The umbrella is broken. The umbrellas are broken.
• El sacapuntas está en el cajón. Los sacapuntas están en el cajón. — The pencil sharpener is in the drawer. The pencil sharpeners are in the drawer.

In other compounds, the element that carries the main noun meaning takes the plural ending. For lexicalized compounds such as ferrocarril and baloncesto, the complete word is pluralized normally.

• El ferrocarril llega tarde. Los ferrocarriles llegan tarde. — The train arrives late. The trains arrive late.
• El baloncesto es popular. Los baloncestos son populares. — Basketball is popular. The basketballs are popular.

Some compound nouns are invariable in form even though their meaning can be singular or plural, as with rascacielos and cumpleaños.

• El rascacielos es alto. Los rascacielos son altos. — The skyscraper is tall. The skyscrapers are tall.
• Mi cumpleaños es mañana. Mis cumpleaños son en verano. — My birthday is tomorrow. My birthdays are in summer.

The general rules have several important exceptions and special cases.

• Nouns ending in unstressed -s or -x usually remain unchanged. The article and other words indicate the number.El lunes es festivo. Los lunes son festivos. — Monday is a holiday. Mondays are holidays.El tórax está sano. Los tórax están sanos. — The thorax is healthy. The thoraxes are healthy.
• Nouns ending in stressed -s generally add -es.El inglés es útil. Los ingleses son útiles. — English is useful. English people are useful.
• Some foreign words and abbreviations may remain unchanged, although usage can vary. For example, góspel is commonly invariable, and CD is often used unchanged as a plural abbreviation.Escucho góspel. Escuchamos góspel. — I listen to gospel music. We listen to gospel music.Compré un CD. Compré dos CD. — I bought one CD. I bought two CDs.
• Some compound nouns are invariable in form, including rascacielos and cumpleaños.El cumpleaños es especial. Los cumpleaños son especiales. — The birthday is special. The birthdays are special.

When a word has an established irregular or variable plural, consult a reliable dictionary if you are unsure.