In Serbian grammar, adjectives play a crucial role in describing and modifying nouns. They are words that provide additional information about the characteristics, attributes or qualities of the noun they are attached to. Adjectives in Serbian have three main forms: masculine, feminine and neuter, which need to agree in gender, number and case with the noun they qualify.

In addition to their main forms, adjectives can also have comparative and superlative forms, allowing for comparison of qualities between two or more nouns. The comparative form is used to compare two nouns, while the superlative form is used to describe the highest degree of a quality in a group of more than two nouns.

Adjectives in Serbian can also be declined based on the case they are used in. Depending on the case, the form of the adjective may change to indicate its role in the sentence, such as nominative, accusative, genitive, dative, instrumental, or locative case.

Understanding the theory of adjectives is crucial for learners of Serbian, as it allows for more accurate and precise communication in both spoken and written forms.