What are adjectives?

We use an adjective to describe the qualities of people, things, places, etc. She’s a young woman.
He's a great singer.
We use an adjective (not an adverb) after 'linking' verbs such as be, become, feel, seem, smell, sound, look, etc. It looks interesting.
It tastes delicious.
His ideas are interesting.
We can use an adjective to describe the object of a sentence. His answer made his boss angry.
Adjectives – common mistakes
Common mistakes Correct version Why?
She was too frighten to say a word.
I am very interesting in this problem.
It was a bored film.
She was too frightened to say a word.
I am very interested in this problem.
It was a boring film.
Many adjectives are participle forms of verbs. The -ed form describes how someone feels (bored). The -ing form describes the person or thing that causes the feeling (boring).
The camera works perfect. The camera works perfectly. We use an adverb (perfectly = adverb, perfect = adjective) when we want to say how we do something.
She married a German, young, tall lawyer. She married a tall, young, German lawyer. Adjectives normally go in the following sequence: size - age - shape - colour - origin - material - purpose.
See also: Stuart’s article ‘When an adjective—not an adverb—should follow a verb’