How do I know whether B2 First wants more than or as...as?

Look at the exact idea the sentence expresses. If it compares a difference, you normally need more/fewer/less + than. If it expresses equality, you need as + adjective/adverb + as. In B2 First this comes up a lot in Part 1, where all four options look logical, and in Part 4, where the key word forces you to rebuild the exact structure. The error is rarely about vocabulary — it's about failing to detect whether the sentence is talking about difference or equality.

Can you say as expensive than in B2 First?

No. That mix is a classic error. In English, as goes with as, not with than: as expensive as. Than appears with comparatives like more expensive than, cheaper than or better than. In the exam, this confusion shows up most when you start with an equality idea and then get dragged along by other options containing than. If you mix the two structures, Cambridge flags it as a clear grammatical error.

Which comparatives appear in B2 First Key Word Transformation?

You usually get reformulations where you have to keep the same meaning using structures like not as...as, more...than, less...than or irregular comparatives like better/worse. The real difficulty isn't just knowing the rule — it's respecting the word limit and not changing the meaning. For example, an idea of inferiority often transforms more naturally with not as...as than with less + adjective. That's exactly where many students slip in Part 4.

What's the difference between less...than and not as...as for B2 First?

Both can express inferiority, but they aren't always used the same way. With adjectives, at B2 it's much more natural to use not as + adjective + as: This printer is not as reliable as that one. Less reliable than also exists, but it can sound more formal or less expected depending on the context. In Part 4, Cambridge tends to reward the most natural structural option for the given key word. Don't automatically translate a 'less... than' idea as less...than without checking what kind of word follows.

Why do I get comparatives wrong if I understand the meaning?

Because in B2 First it's not enough to grasp the general idea. You have to produce the exact architecture: than after a comparative, as...as for equality, and not as...as for the very frequent case of inferiority. Students usually understand the comparison but fail when building it: they drop the second as, mix than with as, or use more with adjectives that already form an irregular comparative, like better. In Part 1 that makes you fall for distractors; in Part 4 it invalidates your whole answer.

Comparative structures in B2 First | Mastery

Where it appears in the exam

What is it?

This competency is about comparing two things in English using difference or equality: more than, less than, fewer than, as...as and not as...as. Many learners lean on a single idea of 'more... than', 'less... than' and 'as... as', but in English the type of word and the complete structure matter much more. The problem is rarely understanding the comparison — it's building it with the correct pair of words.

Why it matters in the exam

In B2 First it shows up above all in Part 1, where a single word changes the whole logic of the gap, and in Part 4, where you have to reformulate without losing the same degree of comparison. If you pick the wrong structure, you don't just lose a word: you lose the exact sense of equality, superiority or inferiority that the exam is measuring.

The cognitive trap

Instinct

"Your instinct mixes the two frames: "this printer is not as fast than the other one""

Once you reach for a comparison, the link 'than' is so automatic that the brain attaches it to any comparative structure, even one that has already opened with 'as'.

Rule

This printer isn't as fast as the other one. / This printer is faster than the other one.

In English you have to choose between two distinct frames: as ... as for equality or, with not, inferiority, and comparative + than for difference. You can't mix them.

Recognition pattern

Which comparative structure do I use

Are you comparing two people, things, actions or results?

YES

Do you mean they're equal in degree?

YES

Use as + adjective/adverb + as: "as useful as", "as carefully as"

NO

Do you mean one thing has a lower degree than the other without changing the focus of the sentence much?

YES

Use not as + adjective/adverb + as, or less/fewer + noun/adjective + than depending on the structure

NO

Use comparative + than: "more efficient than", "better than", "faster than"

NO

This competency doesn't apply: you may need a superlative, an intensifier or a different structure

In the exam, look for the key signal first. The answer follows.

Signals that tell you what to compare

Signal Form

than after the gap You need a comparative, not as

"The new arrangement was more successful than anyone had expected."

Signal Form

as + adjective/adverb + as Expresses equality of degree

"The second speaker was as convincing as the first one."

Signal Form

not as ... as Expresses inferiority very naturally with adjectives and adverbs

"The report was not as clear as the manager had hoped."

Signal Form

good / bad / far in a comparison Check irregular comparatives: better, worse, farther/further

"The updated version is better than the previous one."

Signal Form

plural countable noun Usually wants fewer ... than, not less ... than

"The new policy caused fewer problems than we had predicted."

Signal Form

long adjective like practical, efficient, reliable Normally uses more/less + adjective + than

"The final proposal was more practical than the original draft."

Errors that Cambridge does punish

Wrong

"The printer in the reception area is not as reliable than this one."

Cambridge penalises it because you mix two incompatible structures: as...as and comparative + than.

Right

"The printer in the reception area is not as reliable as this one."

Expresses inferiority with the complete structure not as + adjective + as.

Wrong

"The new system is efficienter than the old one."

It's a comparative-formation error. Not every adjective takes -er.

Right

"The new system is more efficient than the old one."

With a long adjective like efficient, the standard comparative is more + adjective + than.

Wrong

"Our results were as good than we had expected."

The second element of an equality requires as, not than.

Right

"Our results were as good as we had expected."

Here you compare equality between the actual result and the prior expectation.

Wrong

"This solution is more better than the one we tried last month."

Cambridge penalises the double marking of the comparative: you can't use more with better.

Right

"This solution is better than the one we tried last month."

Better is the irregular comparative of good and is very typical in exam contexts.

Wrong

"The second option was less practical that it seemed at first."

The correct link in comparatives is than, not that. It's a very common error from visual habit.

Right

"The second option was less practical than it seemed at first."

Less + adjective + than works well to express a lower degree.

Why your brain gets it wrong

The learner's short circuit

Analyse the trap by exam format

Part 1 — Multiple Choice Cloze

The revised plan turned out to be 1 practical than the original one, even though it looked less ambitious at first.

A as ← your instinct

B more ✓ correct

C so

D much

Many students see a comparison idea and reach for an equality frame, but the gap is already followed by than. That word blocks as. In Part 1, Cambridge pushes you to choose by general meaning; the real trick is to read the structure that's already written, not just the idea of comparing.

The trap in Part 1 isn't the vocabulary, it's the architecture

In this format, the distractors usually sound reasonable if you read fast. With comparatives, the exam exploits the fact that a student understands the comparison but doesn't verify whether the sentence wants as...as or more/less...than.

Strategy

Do a mechanical check: if you see than after the gap, look for a comparative; if you see as after the adjective, complete an equality or, with not, inferiority. Don't decide on semantic intuition alone.

Comparative structures (more than / as...as) is 1 of 82

The exam tests 82 grammar competencies across 19 families. Mastering one is the first step. Automating all 82 is passing.

Tiempos verbales 6

Modales 5

Pasiva y causativa 2

Condicionales 6

Infinitivo, gerundio y participio 5

Énfasis y orden de palabras 4

Oraciones de relativo 4

Reported Speech 4

Comparativos y superlativos 5

Conectores 5

Preposiciones 4

Colocaciones y phrasal verbs 4

Formación de palabras 6

Determinantes y cuantificadores 4

Adjetivos y adverbios 5

Preguntas y negación 4

Patrones verbales 3

Concordancia y ortografía 3

Vocabulario 3

Related competencies

Practise this topic with real exercises

Comparative structures (more than / as...as) in B2 First

Where it appears in the exam

Part 4 — Key Word Transformation

Part 4 — Key Word Transformation

Recognition pattern

The learner's short circuit

Comparative structures (more than / as...as) is 1 of 82