How To Use Spanish Adjectives Ending in -o

How To Use Spanish Adjectives Ending in -o

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Today, we will learn how to use some common adjectives ending in -o in Spanish. Since adjectives agree in gender and number with the noun they describe, it is important to know when the -o ending is correct.


-o ending usually matches masculine nouns

In Spanish, unlike in English, the noun and its adjective have to agree, meaning they must reflect the same gender and number. In most cases, the -o ending indicates that the adjective has taken a masculine singular form. Let’s look at these examples:

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Spicy food can indeed make your labio hinchado!
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In the first sentence, the word cabello is masculine, and therefore the adjectives corto and negro have an -o ending. In the second, the adjective hinchado matches the masculine singular noun labio.

Now let’s consider a different scenario:

We can see that since the word barba is feminine, the adjective does not end in -o. In this case, it ends in -a.


Masculine and plural agreement with -o and -s

Let’s observe how the nouns and the adjectives agree in the following sentences. This time, they reflect both the -o ending of the masculine gender and the -s of the plural number:

Notice how the word dientes in the second example is an irregular masculine form that takes an -e instead of the more common -o ending. 

That’s it! Now you can add your -o ending adjectives to your masculine nouns.


Written by Isabel Matos