Humans are slow animals compared to cheetah, rabbit or deer. Our strength is far less than that of elephants, rhinos or hippos. Emotionally we can be overcome by the fidelity and unconditional love of a dog. Only in language are we clearly superior.
Adjectives are special words , because thanks to them we can know what a person is like, if an object belongs to someone or not, if we are near or far from something, if we are first, second or third. In short, there is an adjective for each situation.
Allies of the noun
Everything that surrounds us has one dimension or another depending on the intervention of qualifying adjectives. Things are pretty or ugly, people are nice or unpleasant, animals are dangerous or harmless.
We cannot say anything about a thing, person or living being if we do not resort to a qualifying adjective. Some serve to describe in a positive and complimentary way and others for the opposite.
Mine, yours and theirs
The words we use to indicate possession are possessive adjectives. Thanks to them we know how to identify that this is mine, yours or theirs. They are placed before or after the noun (that is my dog or that book is mine).
Talking about distances between objects and people
Demonstrative adjectives serve to communicate how far we are from something or someone. If I say that this table is dirty, I am indicating that said object is within walking distance, while if I affirm that that neighbor is unfriendly, I am saying that the aforementioned person is very far from my position.
They provide imprecise information about the noun they accompany. If I say that any day I am going to see you I am not saying anything concrete. If I comment that I have a lot or little money, I also do not provide accurate information about my economy.
By stating that each person is different I do not mean anyone in particular. If I tell a friend that we will talk another day, it is not known when that day will be. Indefiniteness is the characteristic of these adjectives.
Putting a little numerical order
Numeral adjectives give precise information on quantitative questions. We use them to count things or people. While the undefined are vague, they say something precisely (one hundred soldiers, a friend, or four children).
On the other hand, the adjectives cardinal numerals allow to order situations of numerical type (it is my twentieth birthday). Partitive adjectives numerals indicate what part of something we are talking about (a third of my wealth or half of my food).