How do I know if a noun is masculine or feminine?

A crash course in noun gender...

Spanish is very kind in that it's usually easy to work out whether a noun is masculine or feminine.

If it ends in an O it is masculine.

If it ends in an A it is feminine.

E.g. Mundo (world), Trabajo (job), Perro (dog) are all masculine, and Casa (house), Palabra (word), Hora (hour) are all feminine.

We use the article El for a masculine noun, and La for a feminine noun. (this is why, when you learn a new noun, you should always write the article next to it - e.g. write 'la casa' not just 'casa'.)

If a word ends in another letter, for example Mujer (woman) or País (country), it could be either.

There are lots of patterns to look out for - e.g. nouns ending in 'ión' like Opinión (opinion) and Construcción (building/construction) tend to be feminine.

Sometimes you can work out whether it's masculine or feminine from what it is e.g. Hombre (man) is a masculine noun.

Here are a few examples:

Questión (question) = feminine

Madre (mother) = feminine

Ciudad (city) = feminine

Aire (air) = masculine

Arte (art) = masculine

País (country) = masculine

There are, of course, some irregulars, where the noun ends in an O but is feminine, or ends in an A but is masculine:

La mano (hand) = feminine

El programa (programme) = masculine

El día (day) = masculine