English uses like for resemblance and as ... as for equal degree. Persian makes the same conceptual distinction with different structures. مثل mesl-e introduces something used as a model of similarity: “like X.” به اندازهی be andâze-ye literally means “to the measure of X” and places two things at the same point on a named scale: “as adjective as X.”
Two constructions, two claims
| Construction | Neutral pattern | What it claims |
|---|---|---|
| similarity | X + مثلِ Y + predicate | X resembles Y in the relevant way |
| equal degree | X + به اندازهی Y + adjective + copula | X and Y have an equal degree of the adjective |
| negative similarity | X + مثلِ Y + نیست | X is not like Y |
| negative degree | X + به اندازهی Y + adjective + نیست | X is not as adjective as Y |
Ordinary spelling does not show the linker after consonant-final مثل, but it is pronounced mesl-e. In اندازهی, final silent ه requires the written linker هی with a ZWNJ. See ezafe after silent he for the spelling principle.
مثل: resemblance, not measured equality
مثل + noun/pronoun means “like” or “similar to.” The dimension of similarity can be stated by an adjective, inferred from the situation, or expressed through an entire event. It does not by itself assert exact equality on a scale.
این پارچه مثل ابریشم است، اما ارزانتر است.
in pârche mesl-e abrisham ast, ammâ arzân-tar ast.
This fabric is like silk, but it is cheaper. (neutral standard)
صدای این خواننده مثل صدای پدرش گرم است.
sedâ-ye in khânande mesl-e sedâ-ye pedar-ash garm ast.
This singer's voice is warm like his father's. (neutral standard)
In the second example, گرم identifies the relevant resemblance, but “warm like” does not measure two voices and certify exact equality. It gives the father's voice as a comparison image.
مثل also compares behavior or events:
او مثل یک مدیر باتجربه مشکل را آرام حل کرد.
u mesl-e yek modir-e bâ-tajrobe moshkel râ ârâm hal kard.
He or she solved the problem calmly like an experienced manager. (neutral standard)
The [formal] alternative مانند often appears in reports and polished prose; مثل is neutral and extremely common in both conversation and ordinary writing.
به اندازهی: equal degree on a named scale
Use به اندازهی + standard + adjective when the comparison is specifically about degree. The adjective appears after the comparison phrase, immediately before its copula in the neutral predicate order.
این اتاق به اندازهی آن یکی روشن است.
in otâq be andâze-ye ân yeki rowshan ast.
This room is as bright as the other one. (neutral standard)
سارا به اندازهی خواهرش قدبلند است.
Sârâ be andâze-ye khâhar-ash qadboland ast.
Sara is as tall as her sister.
Here قدبلند names the scale explicitly: the comparison concerns height, not some other resemblance between Sara and her sister. Persian also has the compact adjective همقد “of the same height,” but به اندازهی ... قدبلند makes the equative structure visible.
این کار به اندازهی پروژهی قبلی سخت نبود.
in kâr be andâze-ye prozhe-ye qabli sakht nabud.
This job wasn't as hard as the previous project. (neutral standard)
English repeats as on both sides of the adjective. Persian does not: one measure phrase به اندازهی ... precedes the adjective. There is no second particle after it.
A minimal meaning contrast
Compare broad similarity with equality on one property:
این پارچه مثل ابریشم است.
in pârche mesl-e abrisham ast.
This fabric is like silk. (overall resemblance is relevant)
این پارچه به اندازهی ابریشم نرم است.
in pârche be andâze-ye abrisham narm ast.
This fabric is as soft as silk. (equal degree of softness is asserted)
The second sentence says nothing about color, origin, or material; it compares softness. The first can invite any contextually relevant resemblance. This difference matters whenever precision matters, especially in reviews, measurements, and technical descriptions.
Negative equatives
Negating مثل denies resemblance. Negating به اندازهی ... adjective denies the equal-degree description and commonly implies that the subject lies lower on the scale.
این دو طرح مثل هم نیستند؛ فقط رنگشان یکی است.
in do tarh mesl-e ham nistand; faqat rang-eshân yeki ast.
These two designs are not alike; only their color is the same. (neutral standard)
این مسیر به اندازهی جادهی ساحلی شلوغ نیست.
in masir be andâze-ye jâde-ye sâheli sholugh nist.
This route isn't as busy as the coastal road. (neutral standard)
Strictly speaking, “not equal in busyness” could permit either a lower or higher degree. In normal scalar conversation, however, the unmarked به اندازهی ... شلوغ نیست reading is “less busy.” If direction could matter, use an explicit comparative:
این مسیر از جادهی ساحلی خلوتتر است.
in masir az jâde-ye sâheli khalvat-tar ast.
This route is quieter than the coastal road. (explicit direction)
Negative مثل is not an indirect way to say “less adjective.” مثل هم نیستند contrasts identities or patterns; به اندازهی ... نیست targets degree.
Position and scope
In the neutral clause, the comparison phrase comes before the adjective: X به اندازهی Y مهم است. Moving it after the copula produces an afterthought and is not the basic learner pattern. Degree words can precede the adjective, but they change the claim: کموبیش به اندازهی “more or less as” weakens equality, while دقیقاً به اندازهی “exactly as” strengthens it.
این میز کموبیش به اندازهی میز قبلی بزرگ است.
in miz kam-o-bish be andâze-ye miz-e qabli bozorg ast.
This table is more or less as large as the previous table. (neutral standard)
The adverb کموبیش modifies the equality relation, not merely بزرگ. Persian word order makes that scope natural by placing it before the measure phrase.
For an attributive description, a relative clause is often clearer than packing a long equative after a noun: میزی که به اندازهی این بزرگ است “a table that is as big as this one.” This avoids a heavy ezafe chain.
A short dialogue
اتاق جدید مثل اتاق قبلی است؟
otâq-e jadid mesl-e otâq-e qabli ast?
Is the new room like the previous one? (careful spoken standard)
کموبیش، ولی به اندازهی آن روشن نیست.
kam-o-bish, vali be andâze-ye ân rowshan nist.
More or less, but it isn't as bright as that one. (careful spoken standard)
The question asks about overall similarity; the answer narrows the comparison to brightness.
Common Mistakes
1. Omitting the written ezafe after اندازه
❌ این سالن به اندازه آن روشن است.
Incorrect standard spelling — final silent ه takes the visible linker هی.
✅ این سالن به اندازهی آن روشن است.
in sâlon be andâze-ye ân rowshan ast.
This hall is as bright as that one.
2. Copying both English “as” words
❌ این اتاق به اندازهی آن روشن به اندازه است.
Incorrect English calque — Persian uses one به اندازهی phrase before the adjective.
✅ این اتاق به اندازهی آن روشن است.
in otâq be andâze-ye ân rowshan ast.
This room is as bright as that one.
3. Adding comparative ـتر to an equality statement
❌ نیما به اندازهی برادرش بلندتر است.
Incorrect for equality — بلندتر asserts a comparative difference.
✅ نیما به اندازهی برادرش قدبلند است.
Nimâ be andâze-ye barâdar-ash qadboland ast.
Nima is as tall as his brother.
4. Using مثل when exact degree is the point
❌ این طناب مثل آن طناب بلند است.
exactly as long as that rope
Imprecise for the intended equal measurement — مثل only supplies a resemblance model.
✅ این طناب به اندازهی آن طناب بلند است.
in tanâb be andâze-ye ân tanâb boland ast.
This rope is as long as that rope.
Key Takeaways
- مثلِ Y expresses resemblance; it does not guarantee equal degree.
- X به اندازهی Y adjective است explicitly places X and Y at the same degree.
- Write the visible ezafe in اندازهی and pronounce the invisible linker in مثلِ.
- Negative مثل هم نیستند denies likeness; به اندازهی ... نیست normally conveys “not as ... as.”
- Keep the comparison phrase before the adjective in neutral order.
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