Nouns
A noun is a word used to identify a person, place, thing, or idea. In Spanish, nouns have gender, feminine or masculine. Also, they have number, singular or plural.
Masculine nouns Femenine nouns
Ending in “o”: el abuelo Ending in “a”: la abuela
el número la computadora
Ending in “or”: el profesor Ending in “ora”: la profesora
Ending in “ista”: el pianista Ending in “ista”: la pianista
Ending in “ma”: el problema Ending in “ción”: la canción
Ending in “s”: el país Ending in “dad”: la universidad
There are some exceptions to the rules of gender:
la mano, ending in “o”, but it is feminine
el mapa, ending in “a”, but it is masculine
Plural of nouns
If a noun ends in a vowel: add “s”: el abuelo – los abuelos
If a noun ends in a consonant add “es”: el lápiz – los lápices
When the plural refers to two or more nouns of different genders, use the masculine plural form:
3 niños + 4 niñas = 7 niños
(masculine) + (femenine) = (Masculine plural)
References:
http://StudySpanish.com/grammar/lessons/genoun1
http://StudySpanish.com/grammar/lessons/genoun2
José A. Blanco. (2012). Vistas: Introducción a la Lengua Española. Boston Massachusetts: Vista Higher Learning