Like many languages in the world, Spanish has definite distinctions placed on gender. Depending on how you take it, learning Spanish is either hard or easy to master.
Some people think it is an added burden. Some people on the other hand think it helps them learn the language better because seeing a gender-specific attribute to a word automatically tells them the right qualifiers.
Like most Latin-based languages (English included), Spanish makes the maleness or femaleness of man and animals (and some things) an inherent characteristic. This determines the form of the adjectives that describe them.
Consequently, most nouns are classified as either feminine or masculine. However, there are certain things we think as masculine but are actually feminine. This is also true in the case of feminine nouns which are masculine.
Others think the gender attributes in Spanish as simple classifications more than anything else. This is because unlike the other European languages, Spanish has no neuter nouns. Some pronouns are neuter (lo and ello) but used only under limited circumstances.
Ordinarily, all nouns and adjectives ending in -O (and -OS in the plural form of adjectives) are classified as masculine. Nouns and adjectives that end in A (and AS for the plural adjectives) are feminine.
Following this, all masculine nouns go with masculine adjectives and articles, and feminine nouns have their own feminine adjectives and articles. (The articles in English are the words A, AN and THE.)
If you want a pronoun to describe a masculine noun, it has to be a masculine pronoun as well. This rule also applies to feminine nouns, pronouns, and adjectives.
However, there are many adjectives in Spanish that do not have separate masculine or feminine forms. And as in all things, there are exceptions to the rules.
One common example is CADA DIA which means each day. DIA (day) is a masculine noun while CADA (each) can either be a feminine or masculine.
You can see this in dictionaries where there are notations F or M to indicate gender. This is because sometimes the gender of the nouns cannot be ascertained simply by looking or knowing its meaning.
In most dictionaries, nouns are already accompanied by their articles EL (masculine) and LA (feminine) which both means THE in English.
The following are examples how a nouns gender affects the usage of the other words.
the man el hombre (masculine article EL, masculine noun HOMBRE)
the woman la mujer (feminine article LA, feminine noun MUJER)
a man un hombre (masculine article UN, masculine noun HOMBRE)
a woman una mujer (feminine article and noun)
the men los hombres (plural form of masculine article and noun)
the women las mujeres (plural form of feminine article and noun)
the fat man el hombre gordo (masculine article, adjective GORDO, and noun)
the fat woman la mujer gorda (feminine article, adjective GORDA, and noun)
some men unos hombres (masculine determiner and noun)
some women unas mujeres (feminine determiner and noun)
He is fat El es gordo. (masculine pronoun EL, masculine adjective)
She is fat Ella es gorda. (feminine pronoun ELLA, feminine adjective)
These samples clearly show how gender plays a big part in modifying words and make them right together in a sentence. Learning Spanish is a challenge.