Every substantive ist either masculin or femenin. The masculin substantives use the article "el" and the femenin the article "la":
| Masculin | Femenin |
| El coche | La caja |
The are other substantives which can be used in masculin or in femenin:
| Masculin | Femenin |
| El niño | La niña |
| El gato | La gata |
| El profesor | La profesora |
As an informal rule, we could say that every substantive which ends in "a" is femenin and every substantive which ends in "o" is masculin. There are of course exceptions (el sofa, la moto) but you can normally apply the rule with high probability of sucsess.
The plural
Building the plural from spanish words is very easy because you only have to add "-s" or "-es" to the end of the word depending if it ends with vowel or with consonant. The articles for plural change to "los" for masculin and "las" for femenin:
| Singular | Plural |
| el coche | los coches |
| la caja | las cajas |
| el gato | los gatos |
| el profesor | los profesores |
| la profesora | las profesoras |
| el ventilador | los ventiladores |
| la televisión | los televisiones |
| la raíz | las raices |
The last word (raíz) changed the "z" to "c". Words which end in "z" loose the letter and change it to "c" before the addition of "es".
The undefined article
We use "un" and "una" for the undefined singular substantives and "unos" and "unas" for the undefined plural substantives:
| Singular | Plural | |
| Masculin | un coche | unos coches |
| un gato | unos gatos | |
| Femenin | una profesora | unas profesoras |
| una caja | unas cajas |
Vocabulary used in the examples:
caja - box
coche - car
gato,gata - cat
moto - motorbike
niño - boy
niña - girl
profesor,profesora - teacher
sofa - sofa
television - television
ventilador - ventilator
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