Simple explanation
What does as … as mean? We use as … as when we compare two people, things, places, or situations and say that they are equal or similar in one particular way. For example, Tom is as tall as Ben means that Tom and Ben are the same height, or that their height is being described as equal. The positive form To express equality, put an adjective between two as words: as + adjective + as. The first as comes before the adjective, and the second as introduces the person or thing used for comparison. For example: This room is as bright as the kitchen. The negative form: not as … as Use not as … as when the first person or thing has less of a particular quality than the second. My car isn't as fast as yours means that my car does not have the same speed as your car. In this comparison, your car is faster. Questions with as … as You can also use as … as in questions. With be, put the correct form of be before the subject: Is your bag as heavy as mine? With other verbs, follow the normal question pattern: Does Leo run as fast as Max? Use the base form of the adjective The adjective between as and as stays in its base form. Do not use a comparative form. Say as tall as, not as taller as. With longer adjectives, say as expensive as, not as more expensive as. Comparisons with adverbs As … as can also compare how people do something. In this case, an adverb can appear between as and as. For example, She speaks as clearly as her teacher compares how clearly two people speak.
Grammar formula
Positive comparison with be
subject + be + as + adjective + as + comparisonEmma is as tall as Lisa.
Negative comparison with be
subject + be + not + as + adjective + as + comparisonThis bag isn't as heavy as mine.
Question with be
be + subject + as + adjective + as + comparison?Is your room as quiet as mine?
Comparison with an adverb
subject + verb + as + adverb + as + comparisonSam runs as fast as Leo.
Question with another verb
do/does + subject + base verb + as + adverb + as + comparison?Does Nina study as hard as Tom?
Core rules
- 1
Expressing equality
Use as + adjective + as when two people or things have the same or a similar degree of a quality: Mia is as tall as Eva.
- 2
Expressing inequality
Use not as + adjective + as when the first person or thing has a lower degree of the quality: This room isn't as large as that one.
- 3
Keep the adjective in its base form
Do not add -er and do not use more between as and as. Use as cheap as and as interesting as, not as cheaper as or as more interesting as.
- 4
Questions with be
Move be before the subject to form a question: Is the new café as busy as the old one?
- 5
Questions with other verbs
Follow the normal question pattern with other verbs. In the present simple, use do or does: Does Anna work as hard as Mia?
- 6
Comparing actions
Use an adverb between as and as when you compare how an action is performed: He drives as carefully as his father.
Useful examples
My brother is as tall as my father.
My brother and my father are the same height.
As tall as expresses equality in height.
This restaurant is as busy as the café next door.
The restaurant and the café have a similar number of customers.
Busy is the quality being compared.
Your laptop is as expensive as mine.
Your laptop and my laptop cost about the same amount.
Mine replaces my laptop and avoids repetition.
The blue coat isn't as warm as the black one.
The blue coat is less warm than the black coat.
Not as warm as shows inequality.
Today isn't as cold as yesterday.
Yesterday was colder than today.
The comparison is between the temperature on two different days.
Is your new apartment as quiet as your old one?
Are your new and old apartments equally quiet?
Because the sentence uses be, is comes before the subject in the question.
This exercise is as easy as the first one.
This exercise and the first exercise have the same level of difficulty.
Easy stays in its base form; we do not use easier.
The train wasn't as fast as I expected.
The train was slower than I expected it to be.
A clause can follow the second as.
Daniel runs as fast as his brother.
Daniel and his brother run at the same speed.
Fast describes how Daniel runs.
I can't cook as well as my mother.
My mother cooks better than I do.
Well describes how successfully someone cooks.
Does Nina study as hard as you?
Do Nina and you put the same amount of effort into studying?
Does is used because study is the main verb in a present simple question.
The second film wasn't as interesting as the first.
The first film was more interesting than the second film.
Wasn't as interesting as expresses inequality in the past.
Common mistakes
- ❌ Alex is as taller as Ben. ✅ Alex is as tall as Ben. Use the base form of the adjective between as and as. Taller is a comparative form.
- ❌ This car is as more expensive as that car. ✅ This car is as expensive as that car. Do not use more inside an as … as comparison. Expensive stays in its base form.
- ❌ My bag isn't heavy as yours. ✅ My bag isn't as heavy as yours. The negative pattern still needs both as words: not as + adjective + as.
- ❌ Is your sister tall as you? ✅ Is your sister as tall as you? An equality comparison needs the complete as + adjective + as structure.
- ❌ She runs as faster as her friend. ✅ She runs as fast as her friend. Do not use the comparative faster inside the as … as structure. Use the base form fast.
- ❌ Does Tom works as hard as Anna? ✅ Does Tom work as hard as Anna? After does, the main verb must be in its base form: work, not works.
Learning tips
- Think of as … as as a frame: as + adjective or adverb + as.
- In a not as … as sentence, the first person or thing usually has less of the quality being compared.
- Never use a comparative form such as taller, cheaper, or more interesting between the two as words.
- After the second as, you can use a noun, pronoun, or a short clause.
- Use words such as one, ones, mine, and yours when they help you avoid repeating the same noun.
- When you form a question, keep the normal English question word order; the as … as structure itself does not change.
Practise this topic
Interactive exercises for this topic are coming soon.
PlannedRelated grammar
Related dictionary words
Frequently asked questions
When should I use as … as instead of a comparative with than?
Use as … as when you want to express equality or similarity. Use a comparative with than when one person or thing has more or less of a quality, for example taller than.
What exactly does not as … as mean?
It means that the first person or thing has less of the quality being compared. For example, A isn't as big as B means that A is smaller than B.
Can I say as taller as or as more expensive as?
No. Use the base form between as and as: as tall as and as expensive as.
Can as … as be used with verbs?
Yes. You can use an adverb to compare how two people perform an action. For example: She runs as fast as her brother.
Why do we sometimes use as well as instead of as good as?
Good is normally an adjective, while well is commonly an adverb that describes how an action is performed. For example, She sings as well as her sister compares how the two people sing.
How do I make questions with as … as?
Follow the normal English question pattern. With be, you can ask Is your room as big as mine? With another verb, use the appropriate auxiliary, for example Does he work as hard as you?