Uses of adjectives

 Adjectives add more features to the nouns, in English they always precede the noun and they have no gender (masculine nor feminine) nor number (singular or plural), but they can be graded in the comparative or superlative forms if the adjectives are short, if they have got only one or two syllables, the adjectives from three syllables onwards just place the word "more +adjective+than" (más Adj. que).

There are many types of comparisons in sentences using adjectives. The comparison of superiority always follow the following structure: A  + verb + short adj.-er  than / more long adjective than+   B

The short adjectives ending in only a consonant, they double last consonant and add-er: big= bigger,

 fat= fatter, thin= thinner. Also the final "y" is changed to "i" in adjectives: funny= funnier , ugly= uglier.

A or B are the two people, animals or things that are being compared. There are examples here below:

"Our kids are smarter than theirs. Crows are more intelligent than ostriches. Cars are faster than horses."

However, there are irregular adjectives which are here below:

good = better (mejor) = the best (el/la mejor)

bad= worse (peor) = the worst (el/la peor)

far= farther/further (más lejos) = the farthest/ furthest (el/la más lejano/a)

old= elder (mayor en la familia o grupo)= the eldest (el mayor en la familia...).

There are adjectives which are exceptions in these rules because they can be graded either as short or long, for example "modern, narrow, clever, quiet. fierce, stupid, lonely, unhappy, mindless, boring, bored, etc.

There are comparisons of equality in which all parts are equal in relationship with the adjective, they always have the structure "as...adjective...as" or "not as...adj...as" (tanto como) to express the negative.

Examples: "The rabbits are as cute as the kittens. The wardrobe is not as expensive as the chair."

 There are comparisons of inferiority too by means of the word "less" using the same structure for both short and long adjectives. Example:"My sister is less shy than me. He is less genereous than his parents"

Whenever we want to express the adjective in the maximum grade we use the superlative forms which are form adding -est to the short adjectives or "the most" before the long adjectives (three syllables onwards). Always remind to use the definite article "the" before the short adjective (-est) or "the most".

Examples:"His horse was the fastest in the race. She was the prettiest girl in town. My pet is the saddest"

"The red clown is the funniest in the circus. The French student is the most talkative in the class."

Also there are some adverbials like "too" and "enough" which are used with adjectives, we can use

too + adj. to express a lot (demasiado). Examples: "She eats too much sugar. The jeans are too small."

We can use "enough" before adjectives to express "sufficiently"(suficientemente). 

Examples: "The girls are not old enough for the contest. The kid is big enough to play football." 

There are many expressions in English using these structures such as:

"better late than never" (mejor tarde que nunca), "as busy as a bee"(tan ocupado como una abeja), "the sooner the better" ( cuanto antes mejor).