An adjective is part of speech that modifies a noun or pronoun. Adjectives are sometimes confused with adverbs which might modify just about every thing else. Some examples:

“The massive tree stood within the entrance yard.”

“Dogs are very keen on yellow hearth hydrants.”

“The keys are on the oak desk.”

Possessive pronouns (my, his, her, and so forth) can be used as adjectives in sure conditions. For instance:

“I wish to share my sweet with you.”

In some circumstances, sure phrases (this, that, which, what, and so forth) can be used as adjectives. Examples:

“This e-book is excellent.”

“Which pony would you like in your birthday?”