1. An adjective is a word that describes a noun or pronoun.

1. Adjectives modify nouns or pronouns by providing more information about their characteristics or qualities.

1. Adjectives can be used to answer questions such as "What kind?", "Which one?", and "How many?"

1. Some examples of adjectives include "happy," "sad," "big," "small," "red," "yellow," and "exciting."

1. Adjectives can come before the noun they modify, or they can follow a linking verb such as "be," "seem," or "become."

1. Adjectives can also be used to compare things. This is done using comparative and superlative forms.

1. Adjectives can be modified by adverbs, which provide more information about the adjective. For example: – "She sings beautifully." (The adverb "beautifully" modifies the adjective "beautiful.")

1. Adjectives can also be used in a series to describe a noun. For example: "The tall, handsome, young man walked by." (The adjectives "tall," "handsome," and "young" describe the noun "man.")

Some adjectives are gradable, which means they can be used to describe the degree or intensity of a quality.  

Other adjectives are non-gradable, which means they cannot be modified with intensifiers. These adjectives often describe a fixed or inherent characteristic of a noun. For example 

Some adjectives are proper adjectives, which are formed from proper nouns. These adjectives often begin with a capital letter.  

It's important to choose the right adjective for the context and meaning you want to convey.