Simple explanation
What is an adjective? An adjective gives information about a noun or describes what a person or thing is like. In a quiet room, quiet describes the noun room. Adjectives often come before nouns, but they can also come after be and common linking verbs such as look, feel, and seem. What is an adverb? An adverb can give more information about an action. At A2 level, one of the most useful types tells us how something happens. In She speaks quietly, quietly tells us how she speaks. Adverbs can have other functions too, but describing the way an action happens is the main focus of this lesson. How can you tell the difference? First ask what the word is describing. If it describes a noun or tells you what a person or thing is like, you usually need an adjective. If it tells you how someone does something, you usually need an adverb. Compare He is careful with He drives carefully. Careful describes he, while carefully describes the action drives. How do we form adverbs with -ly? Many adverbs are formed by adding -ly to an adjective: slow → slowly, careful → carefully, and quiet → quietly. With many adjectives ending in -y, the spelling changes: easy → easily and happy → happily. However, not every adverb follows this pattern. Important exceptions Some words do not change when they are used as adverbs. Fast is a common example: a fast car and drive fast. Another important pair is good and well. Good is normally an adjective, while well is commonly used as an adverb: a good singer but sing well. Where do adjectives and adverbs go? An adjective often comes before a noun: a beautiful garden. It can also follow be or a linking verb: The garden is beautiful. You look tired. An adverb of manner often comes after the verb or after the object: She smiled politely. He speaks English well.
Grammar formula
Adjective before a noun
adjective + nounShe has a beautiful voice.
Adjective after be
subject + be + adjectiveThe children are quiet.
Adjective after a linking verb
subject + look/feel/seem + adjectiveYou look tired.
Adverb describing an action
subject + verb + adverbThe children walked quietly.
Adverb after an object
subject + verb + object + adverbShe speaks English clearly.
Regular adverb formation
adjective + -ly → adverbcareful → carefully
Adjectives ending in -y
consonant + y → consonant + ilyeasy → easily
Core rules
- 1
Use adjectives to describe nouns
Use an adjective when you want to describe a person, place, thing, or other noun. For example, careful describes driver in a careful driver.
- 2
Use adjectives after be
When be connects the subject to a description, use an adjective: The children are quiet. Quiet describes the children, not the action of being.
- 3
Use adjectives after common linking verbs
Use an adjective after verbs such as look, feel, and seem when they describe the subject: You look tired. She feels nervous. He seems happy.
- 4
Use adverbs to describe how actions happen
When you want to explain how someone does something, use an adverb: She answered politely. Politely tells us how she answered.
- 5
Add -ly to form many adverbs
Many adjective-adverb pairs follow the pattern adjective + -ly: slow → slowly, careful → carefully, quiet → quietly, and clear → clearly.
- 6
Change -y to -ily in common forms
With many adjectives ending in consonant + y, change y to i before adding -ly: easy → easily and happy → happily.
- 7
Do not add -ly to fast
Fast can be both an adjective and an adverb. Say a fast train and The train moves fast. Do not use fastly for this meaning.
- 8
Use good and well correctly
Good is normally an adjective: She is a good cook. Well is normally the adverb used to describe an action: She cooks well.
Useful examples
Lisa is a careful driver.
Lisa is a driver who takes care and avoids mistakes or danger.
Careful is an adjective because it describes the noun driver.
Lisa drives carefully.
Lisa drives in a careful way.
Carefully is an adverb because it describes how Lisa drives.
The baby is quiet.
The baby is not making much noise.
Quiet is an adjective describing the baby after be.
The baby is sleeping quietly.
The baby is sleeping without making much noise.
Quietly describes how the baby is sleeping.
This is an easy question.
This question is not difficult.
Easy is an adjective describing the noun question.
I can answer this question easily.
I can answer this question without difficulty.
Easily describes how the action can be done.
You look tired today.
You seem tired today.
Tired is an adjective after the linking verb look.
Please speak slowly.
Please speak at a low speed.
Slowly describes how the person should speak.
My brother is a fast runner.
My brother is a runner who moves at high speed.
Fast is an adjective because it describes runner.
My brother runs fast.
My brother runs at high speed.
Fast is an adverb here and does not need -ly.
Emma is a good cook.
Emma is good at cooking.
Good is an adjective describing the noun cook.
Emma cooks very well.
Emma is very good at cooking.
Well is an adverb describing how Emma cooks.
He gave me a quick answer.
He answered me after a short time.
Quick is an adjective describing the noun answer.
He answered my question quickly.
He answered my question in a short time.
Quickly is an adverb describing the action answered.
The teacher explained the problem clearly.
The teacher explained the problem in a way that was easy to understand.
Clearly describes how the teacher explained the problem.
She feels nervous before exams.
She is nervous before exams.
Nervous is an adjective because feel is a linking verb here and describes her state.
Common mistakes
- ❌ She is a carefully driver. ✅ She is a careful driver. Driver is a noun, so it needs the adjective careful. Carefully is an adverb.
- ❌ He drives very careful. ✅ He drives very carefully. The word describes how he drives, so the adverb carefully is needed.
- ❌ She sings very good. ✅ She sings very well. The word describes the action sings. Well is the usual adverb for this meaning, while good is an adjective.
- ❌ My father drives fastly. ✅ My father drives fast. Fast can already function as an adverb. Fastly is not used to mean at high speed.
- ❌ You look tiredly. ✅ You look tired. Look is a linking verb here. Tired describes the subject, so an adjective is needed.
- ❌ He answered the question easy. ✅ He answered the question easily. The word describes how he answered. The adverb formed from easy is easily.
- ❌ The children are quietly. ✅ The children are quiet. Quiet describes the state of the children after are, so an adjective is needed.
Learning tips
- Ask what the word describes before choosing its form. This is more reliable than simply looking for -ly.
- If a word directly describes a noun, use an adjective: a slow bus, a careful student, an easy test.
- If you are answering the question How does someone do it?, you often need an adverb: slowly, carefully, easily.
- Remember good and well as a useful pair: a good player but play well.
- Learn fast as an important exception: a fast car and drive fast.
- After be, look, feel, and seem, use an adjective when you are describing the subject.
- Not every word ending in -ly should automatically be treated as an adverb, and not every adverb ends in -ly. Focus on the word's job in the sentence.
Practise this topic
Interactive exercises for this topic are coming soon.
PlannedRelated grammar
Related dictionary words
Frequently asked questions
How do I know whether to use an adjective or an adverb?
Look at what you want to describe. If you are describing a noun or the state of a person or thing, you usually need an adjective. If you are describing how an action happens, you usually need an adverb.
Do all English adverbs end in -ly?
No. Many adverbs are formed with -ly, but there are important exceptions. Fast, for example, can be used as both an adjective and an adverb.
Why do we say She sings well instead of She sings good?
Because the word describes how she sings. Good is normally an adjective, while well is the adverb commonly used to describe this action.
Why is You look tired correct instead of You look tiredly?
Look is a linking verb in this sentence. Tired describes the state of the subject, so an adjective is required.
Is fastly the adverb form of fast?
No. When fast means at high speed, the same form is used as both an adjective and an adverb. We say a fast car and drive fast.
Where do adjectives usually go in an English sentence?
Adjectives often come before nouns, as in a quiet room. They can also come after be and linking verbs such as look, feel, and seem: The room is quiet and She looks tired.
Can the same English word be both an adjective and an adverb?
Yes. Fast is a common example. It is an adjective in a fast car and an adverb in drive fast. Its function depends on what it describes.