¡Hola! Me llamo Diego.
Your teacher has invited me today to help clarify your doubts when deciding the gender of words . There are some things you should keep in mind when doing so. Let me explain…

It’s all about understanding that in Spanish, every noun
(person, place or thing) has a gender, and that in Spanish, a noun can be either masculine or feminine.

How are all of these masculine nouns alike?
el abogado el libro el chico el baño

How are all of these feminine nouns alike?
la casa la maestra la chica la doctora

Masculine Nouns generally end in – o
Feminine Nouns generally end in – a.
el /un diccionario el / un secretario
la / una computadora la / una profesora
If you look at both the beginning and the ending of each line…

These two words
(el, la) are called definite articles.
“el" and "la" both mean "the.“ el chico / the boy la chica / the girl

One cannot predict the gender of a noun, except in the case of living creatures. Do not try to analyze the nature of the object, looking for some inherent masculinity or femininity.
It won't work!

Take a guess. Do you think the Spanish word for "dress" is masculine or feminine? You might expect it to be feminine, since a dress is an article of clothing worn by females.
Actually, the word for "dress" is a masculine word: el vestido

Take another guess. Do you think the Spanish word for "necktie" is masculine or feminine?
You might expect it to be masculine, since a necktie is an article of clothing worn by males.
Actually, the word for
"necktie" is a feminine word: la corbata

Nouns that end in -sión ,
-ción , -dad , -tad , & -tud are feminine.
televi sión ciu dad conversac ión liber tad acti tud

A few nouns that end in -ma are feminine, such as la ca ma and la plu ma .
Many nouns that end in -ma are masculine.
el cli ma el poe ma
A few nouns that end in
-o are feminine.
la ma no
Some nouns that end in
-a are masculine.
el problem a el di a

If a noun ends in a vowel, make it plural by adding -s .
libro : libro s señora : señora s
The definite articles ( el , la ) also change in the plural form. They become " los " and " las ." el libro : los libro s la señora : las señora s

If a noun ends in a consonant, make it plural by adding -es.
el profesor : los profesor es la ciudad: las ciudad es

The difference between definite articles and indefinite articles can be observed in the following two sentences:
Give me the chocolate chip cookie.
Give me a cookie, please.
The first sentence speaks of a particular (or definite ) cookie:
The second sentence speaks of any of a number of cookies (or an indefinite cookie):
Imagine a plate full of cookies. There are peanut butter cookies, sugar cookies, gingerbread cookies, and one chocolate chip cookie.

In Spanish, the definite article has 4 forms, depending on whether the noun is… masculine, feminine, singular or plural.
el chico la chica los chicos las chicas