English normally says a difficult problem, not difficult a problem. So why do we also say How difficult a problem is it? and It was too serious a mistake to ignore?
A particular family of English constructions allows a degree word + adjective + a/an + singular count noun: how big a problem, too difficult a task, so serious a mistake, as good a reason, that big a deal.
Linguists have given this family the memorable nickname the BIG MESS construction. The name is playful. The grammar is systematic.
Quick answer: why “how big a problem”?
Start with a big problem. When English asks about the degree of big, how big forms a degree phrase. That degree phrase appears before the article–noun sequence: [how big] [a problem].
The adjective has not moved randomly. It belongs to a larger degree expression.
Ordinary noun phrase versus degree construction
- Ordinary: a serious problem.
- Degree construction: too serious a problem.
- Ordinary: a good student.
- Degree construction: so good a student.
The distinction is ordinary description versus degree-focused description.
Why the article stays after the adjective
The indefinite article still marks the noun phrase. The degree phrase—how big, too difficult, so serious—appears before a problem, a task, a mistake. That produces the unusual order.
“Too difficult a task”
This is too difficult a task for a beginner means the degree of difficulty exceeds what is suitable or workable. Too introduces a threshold, not just intensity.
“So serious a mistake”
It was so serious a mistake that the project had to stop. Here so serious signals a degree that supports a consequence. The degree matters because it explains the result.
“As good a reason as any”
That is as good a reason as any compares degree. The adjective remains inside the comparative degree frame: as good, followed by a reason.
“That big a deal”
Conversational English often says It is not that big a deal. Here that is degree-like: to that extent. Compare that big deal, where that is a demonstrative identifying a particular deal.
Same word. Different grammatical job.
“This big a problem”
I did not realise it was this big a problem. Here this indicates a degree of bigness or seriousness. Compare this big problem, where this identifies a particular problem.
Why singular count nouns dominate
The canonical pattern visibly contains a/an, so it naturally selects a singular count noun: a task, an issue, a problem. Plural nouns require a different structure.
“So” versus “such”
English offers two similar-looking routes:
- so + adjective + a + noun: so difficult a problem.
- such + a + adjective + noun: such a difficult problem.
Do not blend them into *so a difficult problem.
Not every degree word licenses the pattern
English naturally says a very difficult problem, not normally *very difficult a problem. This proves the pattern is construction-specific rather than a general rule allowing any intensifier to pull an adjective before the article.
Current corpus research
A 2025 corpus study by Sommerer and Bohmann examined subtypes with how, however, so, as, too, this and that in Present-Day American English. The subtypes shared architecture but differed in frequency, genre distribution and lexical preferences. The important lesson is that the family is real without every member behaving identically.
Why gradable adjectives fit naturally
The construction favours adjectives that vary by degree: big, serious, difficult, good, unusual, expensive. That connects directly to scalar adjective semantics.
Academic English
Students encounter forms such as how significant a factor, too broad a claim, too weak an explanation and as strong an argument as… in formal prose.
That is too broad a conclusion to draw from one study packages a threshold judgement: the breadth of the conclusion exceeds what the evidence permits.
Science and Mathematics
It is too small a sample to support a reliable generalisation marks a threshold between sample size and evidential adequacy. Mathematics can likewise ask How large a value of x is required?, though a simpler form such as How large must x be? may suit some readers better.
Humanities
It was too fragile a coalition to survive the crisis compresses property, degree and consequence. Historical evidence still has to justify the causal claim.
Reading: reconstruct the ordinary noun phrase
If too complicated a procedure looks strange, first identify procedure, rebuild a complicated procedure, then restore the degree phrase: too complicated a procedure.
Diagnosis before prescription
- *a too difficult question: ordinary adjective order retained. Use too difficult a question.
- *so a serious problem: so and such patterns blended. Choose one.
- *very difficult a task: pattern overgeneralised. Use a very difficult task.
- “that big a deal” misread as a demonstrative: compare with that big deal.
- Student avoids the pattern entirely: unusual order has been mistaken for nonstandard English. Build natural examples.
A practical map
- a serious mistake → How serious a mistake was it?
- a serious mistake → too serious a mistake to ignore
- a serious mistake → so serious a mistake that…
- a serious mistake → as serious a mistake as…
A quiet literary lens
Degree often reveals more than category. A character did not merely make a mistake; they made too public a mistake to hide. The noun tells us what happened. The degree phrase tells us why the consequences changed.
Internal-link opportunities
- Gradable and Scalar Adjectives
- Exclamative Clauses
- Semantic Markedness
- Sentence Ambiguity and Word Placement
Connections eduKateAI can learn
- Degree ↔ adjective: forms such as how, too, so and as build degree phrases with gradable adjectives.
- Degree phrase ↔ noun phrase: the degree–adjective unit appears before a/an + singular noun.
- Lexical licensing ↔ grammar: not every intensifier behaves alike.
- So ↔ such: similar meanings can be packaged through different structures.
- Writing ↔ threshold reasoning: forms such as too broad a conclusion encode that a property exceeds an acceptable limit.
- AI language understanding ↔ construction grammar: the pattern should be recognised as grammar, not corrected as random adjective order.
Research basis
- Sommerer & Bohmann (2025) — BIG MESS constructions in Present-Day American English.
- Current descriptive grammar and corpus work on degree modification and indefinite noun phrases.