"Sleepy" is a correct adjective and can be used in the position.
Adjective and Adverb
English distinguishes between adjectives, which qualify nouns and pronouns, and adverbs, which mainly modify verbs, adjectives, or other adverbs. Not all languages make this exact distinction; many (including English) have words that can function as either. For example, in English, fast is an adjective in "a fast car" (where it qualifies the noun car) but an adverb in "he drove fast" (where it modifies the verb drove).
Adjective
An adjective is word whose main syntactic role is to modify a noun or noun phrase. Its semantic role is to change information given by the noun.
Adjectives are one of the main parts of speech of the English language, although historically they were classed together with nouns. Certain words that were traditionally considered to be adjectives, including the, this, my, etc., are today usually classed separately, as determiners.
Adverb
An adverb is a word that modifies a verb, adjective, determiner, clause, preposition, or sentence. Adverbs typically express manner, place, time, frequency, degree, level of certainty, etc., answering questions such as how?, in what way?, when?, where?, and to what extent?. This function is called the adverbial function, and may be realized by single words (adverbs) or by multi-word expressions (adverbial phrases and adverbial clauses).
Adverbs are traditionally regarded as one of the parts of speech. However, modern linguists note that the term "adverb" has come to be used as a kind of "catch-all" category, used to classify words with various different types of syntactic behavior, not necessarily having much in common except that they do not fit into any of the other available categories (noun, adjective, preposition, etc.)
Adjective
An adjective is a word that describes or modifies a noun or pronoun, giving more information about its qualities, state, or identity. Adjectives are one of the core parts of speech in English, and you use them constantly — to describe people, objects, feelings, and ideas.
What adjectives do
Adjectives typically answer questions like What kind?, Which one?, or How many? They can appear in two main positions:
- Before a noun (called attributive position): a tall building, fresh coffee, three students
- After a linking verb (called predicative position): The soup is hot, She seems tired
Some adjectives work in only one position. For example, main is almost always attributive (the main reason), while asleep is almost always predicative (The baby is asleep).
Examples
- ✅ She wore a red dress. (red modifies dress)
- ✅ The exam was difficult. (difficult follows the linking verb was)
- ❌ She wore a redly dress. (Adverbs like redly don't modify nouns.)
- ✅ He gave me useful advice. (useful modifies the uncountable noun advice)
Adjective order
When you stack multiple adjectives before a noun, English follows a conventional order: opinion → size → age → shape → colour → origin → material → purpose. For example, a lovely small old round brown French wooden serving table — though in real life you'd rarely pile up that many.
Self-check: If your sentence sounds awkward with two adjectives before a noun, try swapping their order. The version that "sounds right" usually follows the standard sequence.
Adjectives vs. determiners
Words like the, this, my, and some were historically grouped with adjectives, but modern grammar classifies them as determiners. Unlike true adjectives, determiners don't have comparative forms (bigger works, but *more the doesn't) and occupy a fixed slot before any adjectives.
Comparatives and superlatives
Most adjectives have comparative and superlative forms used to compare things:
- tall → taller → tallest
- expensive → more expensive → most expensive
To practice these, try Comparatives and Superlatives. You can also build a foundation with Basics. Adjectives and Adverbs. and Basics. Word Order..