1. Choose the scale and standard first
As…as compares the degree of a quality or the manner of an action. Ask what you are comparing, which quality you are measuring and what you are comparing it with. The standard can be another thing, another person's behaviour or an earlier expectation.
Put a modifier before the first as: just, every bit, nearly, not nearly or twice. It changes the meaning of the comparison but does not replace the second as.
subject + verb + modifier + as + adjective/adverb + as + standard of comparison
- subject / S —
- The grammatical subject: who or what the clause is about; the verb agrees with it. In The book was written, the book is the subject, although someone else does the action.
- verb / V —
- A word for an action or state, such as work or be. The pattern determines its form.
- adjective —
- A word describing what someone or something is like: happy, tired, interesting.
- adverb —
- A word adding information about an action, quality or circumstance: slowly, very, often.
The delivery was just as prompt as the company had promised.
The delivery was just as prompt as the company had promised.
The actual promptness is compared with the company's promise, not with another company.
Maya explained the process every bit as clearly as her colleague did.
Maya explained the process every bit as clearly as her colleague did.
Clearly modifies explained; did replaces the repeated explained the process.
2. Just and every bit: emphasising equality
Just as…as emphasises an equal degree. Every bit as…as more strongly rejects an assumed advantage of the other side: fully as much, or not at all inferior. This is useful when the listener underestimates a less familiar option.
Every bit does not indicate a numerical measurement. Every bit as useful is an emphatic claim of equal usefulness, not proof that usefulness has been measured with mathematical precision.
The local workshop is every bit as useful as the national conference was.
The local workshop is every bit as useful as the national conference was.
The speaker rejects the assumption that the size of an event determines its usefulness.
The replacement cable is just as long as the original was.
The replacement cable is just as long as the original was.
Just emphasises equality specifically in length; nothing is said about material or quality.
3. Nearly and not nearly send opposite signals
Nearly as…as and almost as…as indicate being close to the standard. Not quite as…as usually points gently to a small shortfall. Not nearly as…as and nowhere near as…as emphasise a substantial gap: the standard is far from being reached.
Nearly does not assign a universal percentage; what counts as almost depends on the situation. Do not calculate an exact difference from a modifier alone. Nowhere near already carries negative meaning, so an ordinary affirmative verb gives the required pattern: is nowhere near as…
The revised summary is not quite as clear as I would like.
The revised summary is not quite as clear as I would like.
This gently points out a remaining shortcoming rather than condemning the summary sharply.
The recording was not nearly as clear as we had expected.
The recording was not nearly as clear as we had expected.
Not nearly indicates a large shortfall in clarity.
The new room is almost as spacious as the old one was.
The new room is almost as spacious as the old one was.
The spaciousness is close to that of the old room; no exact ratio of floor areas is specified.
4. Twice, three times and half: name a measurable quantity
Twice as…as expresses twice the degree, three times as…as three times the degree, and half as…as half the relevant measure. For clarity, choose an understandable quantity: length, mass, duration, price or amount.
The frame keeps the ordinary adjective or adverb: twice as long, not twice as longer. For cost, twice as expensive or half as expensive is clear; twice as cheap is easily interpreted in different ways, so it is unsuitable for a precise calculation.
Reversing the direction changes the multiplier: if A weighs twice as much as B, B weighs half as much as A. A subjective phrase such as “twice as interesting” can be rhetorical, but without a defined scale it is not a mathematical claim.
The replacement part is twice as heavy as the old part was: 8 kg rather than 4 kg.
The replacement part is twice as heavy as the old part was: 8 kg rather than 4 kg.
Eight divided by four is two; the old part was forms the comparative clause.
The meeting lasted half as long as the organiser had planned: 30 minutes instead of an hour.
The meeting lasted half as long as the organiser had planned: 30 minutes instead of an hour.
Long describes duration; half refers to 30/60, not to the speed of conversation.
5. A clause can follow the second as
The comparative clause names the standard: as we expected, as the guide had said, as she does. An ordinary comparative clause uses statement word order, with the subject before the verb. Do not replace the second as with that or than.
You do not have to repeat the entire action: do/does/did can stand in for it, while be keeps the appropriate form. You can also retain a fuller clause if it improves clarity.
As I expected and as I had expected are often both appropriate when discussing a past result. The Past Perfect more explicitly places the expectation earlier; as…as itself does not require it. With clear context, shorter standards such as as before are possible too.
The scanner works just as quietly as the old one did.
The scanner works just as quietly as the old one did.
Did refers back to the old scanner's operation; the second as completes the frame.
The route was nowhere near as steep as I expected.
The route was nowhere near as steep as I expected.
I had expected is also possible. The important point here is the large difference, not a compulsory tense change.
6. The frame is not limited to one word
An expanded phrase can stand between the two as words: as easy to use as or as good a teacher as. A rule requiring exactly one word between them therefore fails. With a singular noun, the order is special: as + adjective + a/an + noun + as.
Other grammatical comparisons do not become errors merely because they fall outside this frame. Far less reliable than expresses a large difference but does not practise as…as. Not so much X as Y reclassifies something, while the more…the more expresses a relationship of change; these are different tasks.
When checking your work, assess the meaning, degree of difference and form separately. A grammatical sentence may fail to meet the given aim: almost as reliable does not express an explicitly stated large shortfall in reliability.
She is just as good a teacher as her mentor was.
She is just as good a teacher as her mentor was.
Good a teacher is a possible phrase inside the frame; this is a boundary example, not a separate topic in this lesson.
The device is not nearly as easy to use as the brochure suggests.
The device is not nearly as easy to use as the brochure suggests.
Easy to use contains more than one word but is a perfectly natural part of the comparison.
Common mistakes
Incorrect:The hall was not nearly as quiet that we had hoped.
Correct:The hall was not nearly as quiet as we had hoped.
In this comparison, the second as introduces the standard; that does not complete the as…as frame.
Incorrect:This beam is twice as longer as the previous one.
Correct:This beam is twice as long as the previous one.
Inside as…as, use the ordinary form long; longer belongs to another pattern.
Incorrect:The pilot session was just as useful than the full course.
Correct:The pilot session was just as useful as the full course.
Just reinforces equality, and the equality frame requires as, not than.
Incorrect:The new tool works every bit as efficiently as the old one do.
Correct:The new tool works every bit as efficiently as the old one does.
The old one is singular; the substitute for repeated works must be does.