Adjective vs Adverb: How to Tell Them Apart
An adjective modifies a noun or pronoun. An adverb modifies a verb, an adjective, another adverb or a whole sentence. That is the whole distinction, and almost every error in this area comes from applying it to the wrong word.
- She is a careful driver. – careful describes the driver, a noun, so it is an adjective.
- She drives carefully. – carefully describes how she drives, a verb, so it is an adverb.
Adjectives and adverbs at a glance
| Adjective | Adverb | |
|---|---|---|
| Describes | nouns and pronouns | verbs, adjectives, other adverbs, whole sentences |
| Answers | What kind? Which one? How many? | How? When? Where? How often? How much? |
| Usual position | before a noun (a quiet room) or after a linking verb (the room is quiet) | flexible: quietly he left / he left quietly |
| Typical forms | quiet, happy, careful, good | quietly, happily, carefully, well, often, very, soon |
| Comparison | quieter, happiest, more careful | more quietly, most carefully, faster, better |
For the adjective side of this in depth, see what is an adjective.
The working test
Find the word being modified, then ask what part of speech it is.
| If the modified word is a… | You need an… | Example |
|---|---|---|
| noun or pronoun | adjective | a quick reply |
| verb | adverb | replied quickly |
| adjective | adverb | remarkably quick |
| another adverb | adverb | very quickly |
| a whole sentence | adverb | Fortunately, nobody was hurt. |
This is more reliable than looking at endings, because endings lie.
Why -ly cannot be trusted
Many adverbs end in -ly, but plenty do not (very, often, soon, here, never, too), and the reverse does not hold either. These are adjectives:
friendly, lovely, lonely, ugly, silly, costly, deadly, elderly, cowardly, orderly, timely
You cannot say she smiled friendly. These words have no adverb form in normal use, so the idea is rephrased: she smiled in a friendly way. (There is more on this in adjectives ending in -ly.)
A few -ly words work as both: daily, weekly, monthly, early, likely. A daily walk (adjective); I walk daily (adverb). A likely result (adjective); He will likely win (adverb, common in American English; British English prefers probably or very likely).
A second group serves as both adjective and adverb with no change in form:
| Word | As adjective | As adverb |
|---|---|---|
| fast | a fast train | drives fast |
| hard | hard work | works hard |
| late | a late arrival | arrived late |
| early | an early start | started early |
| straight | a straight road | went straight |
| high | a high wall | jumped high |
| far | the far side | didn’t go far |
Adding -ly to some of these creates a different word. Hardly means barely, not with effort – he hardly works is close to the opposite of he works hard. Lately means recently. Highly means very or very well (highly recommended), not physically high. See adverbs without -ly for the full list.
The linking verb exception
After a linking verb – be, seem, become, feel, look, smell, taste, sound, remain, appear, get – the describing word points back at the subject, so it takes the adjective form even though it follows a verb.
- Correct: The bread smells fresh. Not freshly – the bread is fresh; it does not smell in a fresh manner.
- Correct: He looks tired. Not tiredly – unless you mean the act of looking was done wearily (he looked tiredly at the screen).
- Correct: The plan seems reasonable.
Check by substituting is. If the bread is fresh holds, the verb is linking and the adjective is right. The same verb can be linking in one sentence and an action verb in another: She looked angry (her appearance) versus She looked angrily at him (the way she looked).
Good and well, bad and badly
These four cause more trouble than the rest of the topic combined.
| Sentence | Correct because |
|---|---|
| She plays well. | well is an adverb modifying plays |
| She is a good player. | good is an adjective modifying player |
| The soup tastes good. | tastes is linking, so the adjective describes the soup |
| I feel bad about it. | feel is linking, so the adjective describes I |
| He was injured badly. | badly modifies the verb injured |
Well has a double life: it is the adverb partner of good, and it is also an adjective meaning “in good health”. So I am well (healthy) and I am good (fine, or morally good) are both correct. More on these in good vs well and I feel bad or badly.
Drive safe, go slow: flat adverbs
Some adjectives are used as adverbs in short, everyday phrases: drive safe, go slow, think big, play fair, sleep tight. These are called flat adverbs. They are long-established and fine in speech, signs and informal writing. In formal writing, use the -ly form where one exists: drive safely, go slowly. (Play fair and think big have no natural -ly version and are fine everywhere.)
Where adverbs go
Adjectives have fixed slots; adverbs move, and the position can change the meaning.
- Adverbs of manner usually follow the verb or its object: She closed the door quietly. Not She closed quietly the door.
- Adverbs of frequency usually go before the main verb but after be: He often works late. He is often late.
- Focusing adverbs like only and just attach to what they limit: I only ate the cake vs I ate only the cake. See where to put only.
Quick decisions
| Choice | Take | Reason |
|---|---|---|
| drive safe / safely | safely (formal); safe is fine informally | modifies the verb; “drive safe” is a flat adverb |
| runs quick / quickly | quickly | modifies the verb |
| tastes sweet / sweetly | sweet | linking verb, describes the subject |
| did good / well | well | modifies did |
| a real / really nice day | really | modifies the adjective nice (“real nice” is informal American speech) |
| sounds great / greatly | great | linking verb |
| a beautifully / beautiful painted room | beautifully | modifies the adjective painted |
Practice: adjective or adverb?
- The children were playing (quiet / quietly) in the garden.
- This coffee tastes (strong / strongly).
- She answered the question (correct / correctly).
- He is a (careful / carefully) writer.
- The exam was (surprising / surprisingly) easy.
- I didn’t sleep very (good / well) last night.
- They worked (hard / hardly) all weekend.
- Your idea sounds (perfect / perfectly).
Answers: 1. quietly (modifies playing). 2. strong (linking verb). 3. correctly (modifies answered). 4. careful (modifies writer). 5. surprisingly (modifies the adjective easy). 6. well (modifies sleep). 7. hard (hardly would mean “barely”). 8. perfect (linking verb).
When you are unsure, do not guess from the ending. Find the word being described, decide what it is, and the choice follows.
Checked against Merriam-Webster, the Chicago Manual of Style and the AP Stylebook. Spotted an error? Tell us — see our editorial policy.
