“Por” and “para”

When a noun ends in -e, it usually is the same in its masculine and feminine forms: estudiante, elefante.

In order to be sure about the gender of a noun we need to look at the articles that accompany them (el or un are masculine; la or una are feminine). However, you can sometimes tell by their ending:

- nouns that end in -sión, -ción, -dad, -tad, -tud, -umbre are feminine: la tensión, la acción, la cuidad, la lealtad, la costumbre.

- most nouns that end in -a are feminine, but there are a few that are masculine. A lot of them end in -ma: el día, el sofá, el planeta, el periodista, el artista, el mapa el tema, el problema, el teorema, el dilema, el poema, el clima, el programa, el sistema, el idioma, el telegrama.

- most nouns that end in -o are masculine, with very few exceptions: la mano, la soprano, la radio, la moto

A few feminine nouns that start with a and the stress of the word falls on the first syllable actually take the masculine article (el or un), simply beacuse it is easier to pronounce. This only happens when we use the singular form: el agua las aguas el águila las águilas