Adjectives describes the noun's appearance like if it is ugly or beautiful. It also describes the number of the noun like: There are three shells near the coast. ADJECTIVES have an end words like (-able, -ly -al, -ful, -ic, -ical, -less, -some,

They are two curly shells near the coast. (In this sentence there are two adjectives and they are two and curly.)
Shells are lovely.
Shells are big and small.
Shells are adorable.
Shells can be harmful or deadly.