Adjective vs Adverb: How to Tell Them Apart
An adjective modifies a noun or pronoun. An adverb modifies a verb, an adjective, or another adverb. 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.
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 |
This is more reliable than looking at endings, because endings lie.
Why -ly cannot be trusted
Most adverbs end in -ly, but the reverse does not hold. These are all adjectives:
friendly, lovely, lonely, likely, ugly, silly, costly, deadly, elderly, cowardly, orderly, timely
You cannot say she smiled friendly. English simply has no adverb form for these, so the idea must be rephrased – she smiled in a friendly way.
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 |
Adding -ly to these either creates a different word or an error. Hardly means barely, not with effort – he hardly works is close to the opposite of he works hard. Lately means recently, not not early.
The linking verb exception
After a linking verb – be, seem, become, feel, look, smell, taste, sound, remain – 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.
- Correct: The plan seems reasonable.
Check by substituting is. If the bread is fresh holds, the verb is linking and the adjective is right.
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 and I am good are both correct and mean different things.
Quick decisions
| Choice | Take | Reason |
|---|---|---|
| drive safe / safely | safely | modifies the verb |
| 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 |
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.
