When you say "he acts as if he were the boss" or "she looks as if she had seen a ghost," you are comparing a real action to an imagined situation. In Italian, this is done with come se — and come se requires the congiuntivo, with no exceptions, in every register. The choice between the imperfetto and the trapassato of the congiuntivo depends on whether the imagined situation is simultaneous with or anterior to the action being described.
This page explains the rule, walks through the tense pairings, and clarifies why English speakers (whose grammar tolerates either mood after "as if") routinely get this wrong in Italian.
The core rule: come se + congiuntivo, always
The construction is come se + the imperfetto or trapassato of the congiuntivo. The indicative is never permitted, regardless of how factual the speaker's tone seems. Come alone (without se) takes the indicative — that's a different construction, meaning "as" or "like" — but the moment you add se, the comparison becomes hypothetical and the subjunctive is required.
Si comporta come se fosse il padrone.
He acts as if he were the boss. (he isn't)
Mi guarda come se fossi pazzo.
She looks at me as if I were crazy.
Parla come se sapesse tutto.
He talks as if he knew everything.
Mangia come se non avesse mangiato da una settimana.
He's eating as if he hadn't eaten for a week.
Piangeva come se le avessero detto una notizia tremenda.
She was crying as if they had told her terrible news.
The signal is unmistakable: come se introduces an imagined, contrary-to-fact comparison. The speaker is not asserting that the imagined situation is real — quite the opposite. The very point of come se is that the comparison is between a real behaviour and an imagined cause. This is precisely the semantic territory of the subjunctive.
Why the subjunctive is required
Italian shares this construction with the rest of the major Romance languages, and the underlying logic is the same: come se explicitly marks the embedded clause as counterfactual or hypothetical. There is no real-world claim that the imagined situation holds; the speaker uses it only as a yardstick for comparison.
Si comporta come è il padrone.
(Wrong as a hypothetical comparison — without *se*, this means 'he behaves as the boss is/does', a factual reading.)
Si comporta come se fosse il padrone.
He acts as if he were the boss. (correct hypothetical comparison)
The contrast is total: come + indicative compares to a real situation; come se + congiuntivo compares to an imagined one. They are not stylistic variants of each other — they make different claims about reality.
Tense pairing: imperfetto vs trapassato
Once you commit to the subjunctive, the only remaining question is which tense — imperfetto or trapassato. The principle is simultaneity vs anteriority:
- Congiuntivo imperfetto when the imagined situation is simultaneous with (or ongoing at the time of) the main action.
- Congiuntivo trapassato when the imagined situation precedes the main action.
This is the only tense alternation possible after come se in standard Italian. The congiuntivo presente and passato are not used in this construction — even when the main verb is in the present, come se still triggers the imperfetto, never the presente.
| Imagined situation | Tense after come se | Example |
|---|---|---|
| Simultaneous with main action | congiuntivo imperfetto | Mi guarda come se fossi pazzo. (the imagined craziness is happening "now") |
| Anterior to main action | congiuntivo trapassato | Mi guarda come se avessi detto una bestemmia. (the imagined utterance precedes the look) |
Simultaneity → congiuntivo imperfetto
When the main verb is in the present, imperfetto, passato prossimo, passato remoto, or future, and the imagined situation overlaps in time with the main action, the congiuntivo imperfetto is the form to use.
Si veste come se avesse vent'anni.
She dresses as if she were twenty. (the imagined youth is concurrent with the dressing)
Mi parlavi come se non mi conoscessi.
You were speaking to me as if you didn't know me.
Ha reagito come se fosse offeso.
He reacted as if he were offended. (offence concurrent with reaction)
Mi guarderà come se fossi un alieno.
He'll look at me as if I were an alien.
The English equivalent uses were / had — the so-called "subjunctive were" of formal English ("as if I were a king"). Italian is more rigorous: there is no looser indicative variant.
Anteriority → congiuntivo trapassato
When the imagined situation is presented as already completed before the main action, switch to the trapassato. This is most common with sensory and reactive verbs (guardare, parlare, piangere, tremare, reagire) where the speaker imagines an antecedent cause.
Tremava come se avesse visto un fantasma.
He was trembling as if he had seen a ghost.
Mi ha guardato come se avessi appena commesso un crimine.
She looked at me as if I had just committed a crime.
Camminava come se non avesse dormito da giorni.
He was walking as if he hadn't slept for days.
Ridevano come se avessero sentito la barzelletta più divertente del mondo.
They were laughing as if they had heard the funniest joke in the world.
The trapassato signals that the imagined cause precedes the observed effect. Avesse visto un fantasma — the ghost-sighting (imagined) would have happened before the trembling (real).
Tense matrix: which form goes with which main clause
The rule of thumb is simpler than the language sometimes makes it look: come se is locked to the imperfetto / trapassato of the congiuntivo, regardless of the main clause tense. Compare this to ordinary congiuntivo dependence, where the tense of the embedded congiuntivo varies with the matrix verb.
| Main clause tense | Simultaneous comparison | Anterior comparison |
|---|---|---|
| Presente: si comporta | come se fosse | come se fosse stato / avesse visto |
| Imperfetto: si comportava | come se fosse | come se fosse stato / avesse visto |
| Passato prossimo: si è comportato | come se fosse | come se fosse stato / avesse visto |
| Futuro: si comporterà | come se fosse | come se fosse stato / avesse visto |
| Condizionale: si comporterebbe | come se fosse | come se fosse stato / avesse visto |
The constancy of the table is the lesson: regardless of when the main action happens, the come se clause stays in the imperfetto or trapassato of the congiuntivo. There is no come se sia, no come se sia stato — those forms simply do not appear in this construction.
Why English speakers slip
English permits two patterns after "as if":
- "He talks as if he were the boss." (subjunctive — formal, careful)
- "He talks as if he is the boss." (indicative — informal, colloquial)
Both are acceptable English, with the indicative variant especially common in spoken American English. Italian permits only the subjunctive variant. The indicative is not a relaxed conversational option; it is ungrammatical.
❌ Si comporta come se è il padrone.
Wrong — Italian does not have an indicative variant of *come se*.
✅ Si comporta come se fosse il padrone.
Right — *fosse* (cong. imperfetto) is the only correct form.
The transfer error is so persistent that it is one of the most reliable markers of an English-speaking learner. Once you have internalised the rule that come se = subjunctive, your Italian will sound substantially more native.
Equivalent constructions
A handful of expressions behave like come se: they introduce a hypothetical comparison and demand the same imperfetto / trapassato congiuntivo.
- quasi (che) — "almost as if," "as though"
- manco / nemmeno — "as if," in colloquial use, often with negation
- come se non bastasse — "as if that weren't enough" (set phrase, useful as a discourse marker)
Quasi che fosse colpa mia.
As if it were my fault. (slightly literary)
Mi rispose, quasi non avesse sentito la domanda.
He answered me, as if he hadn't heard the question.
Ha perso il treno e, come se non bastasse, ha anche perso il portafoglio.
He missed the train and, as if that weren't enough, he also lost his wallet.
The colloquial manco / nemmeno + congiuntivo is regional and informal but extremely common in central and northern Italian speech:
Mi tratta manco fossi suo dipendente. (informal)
He treats me as if I were his employee.
This pattern drops come and se entirely — the bare subjunctive after manco / nemmeno carries the hypothetical force on its own. It is informal but not vulgar; you'll hear it constantly in conversation.
Set phrases worth memorising
Several expressions built on come se have become near-fixed in Italian:
Faccio come se niente fosse.
I'll act as if nothing were the matter. (set phrase — pretend everything's fine)
Parla come se piovesse.
He talks for the sake of talking. (literally: he talks as if it were raining; idiom for empty chatter)
È come se non fosse mai successo.
It's as if it had never happened.
Mi sento come se avessi corso una maratona.
I feel as if I had run a marathon.
These idiomatic uses are worth memorising whole — they appear constantly in conversation and reading.
Comparison with conditionals
The come se + congiuntivo imperfetto / trapassato pattern is closely related to the protasis ("if-clause") of type-2 and type-3 conditionals. Both express counterfactual or hypothetical situations using the same forms.
| Construction | Example | Function |
|---|---|---|
| Type-2 conditional protasis | Se fossi ricco, comprerei una villa. | Hypothetical condition for a hypothetical result. |
| Type-3 conditional protasis | Se avessi studiato, avrei passato l'esame. | Counterfactual past condition. |
| Come se hypothetical comparison | Spende come se fosse ricco. | Real action compared to a hypothetical situation. |
| Come se trapassato comparison | Spende come se avesse vinto la lotteria. | Real action compared to a counterfactual antecedent. |
The shared morphology is the giveaway: imperfetto and trapassato of the congiuntivo are Italian's all-purpose hypothetical machinery. Se alone makes them conditional; come se makes them comparative.
A note on register
The construction is identical in spoken and written Italian. There is no informal version that uses the indicative; even the most casual speech respects come se + congiuntivo. The only register variation is in the choice of equivalent constructions:
- Formal / written: come se, quasi (che), come se non bastasse
- Informal / spoken: come se, plus manco / nemmeno
- congiuntivo
The colloquial manco / nemmeno version is informal in tone but still requires the subjunctive. There is genuinely no way to express this comparison in Italian without the congiuntivo.
Common mistakes
❌ Mi guarda come se sono pazzo.
Wrong — *come se* never takes the indicative.
✅ Mi guarda come se fossi pazzo.
Right — *fossi* is the cong. imperfetto.
❌ Si comporta come se sia il padrone.
Wrong — *sia* (cong. presente) is not used after *come se*; the construction is locked to imperfetto / trapassato.
✅ Si comporta come se fosse il padrone.
Right — *fosse* (cong. imperfetto) regardless of the present-tense main verb.
❌ Tremava come se vedesse un fantasma.
Wrong — the imagined sighting precedes the trembling, so the trapassato is needed.
✅ Tremava come se avesse visto un fantasma.
Right — *avesse visto* (trapassato) for the anterior imagined cause.
❌ Parla come sa tutto.
Wrong — without *se*, this would mean 'he speaks as he knows everything', which is incoherent. The hypothetical reading needs *come se*.
✅ Parla come se sapesse tutto.
Right — *come se* + cong. imperfetto for the hypothetical comparison.
❌ Mi ha risposto come se non sentiva la domanda.
Wrong — *come se* never takes the imperfetto indicativo, only the imperfetto del congiuntivo.
✅ Mi ha risposto come se non sentisse la domanda.
Right — *sentisse* is the cong. imperfetto.
❌ Faccio come niente fosse stato.
Marked — the standard set phrase is *come se niente fosse*, in the imperfetto, not the trapassato.
✅ Faccio come se niente fosse.
Right — fixed expression in the imperfetto.
Key takeaways
Four points capture the construction:
- Come se always takes the congiuntivo. No exceptions, no register variation. The indicative is ungrammatical here.
- The tense is imperfetto or trapassato. Imperfetto for situations simultaneous with the main action; trapassato for situations anterior to it.
- The matrix tense doesn't matter. Whether the main clause is present, past, or future, come se stays in the imperfetto / trapassato of the congiuntivo.
- English isn't a guide. "As if he is" is fine in English but ungrammatical in Italian. The Italian form maps only to the formal English "as if he were."
For the morphology of the imperfetto del congiuntivo, see Imperfetto del Congiuntivo: Regular Forms and Irregular Forms. For the trapassato, see Trapassato del Congiuntivo. For closely related counterfactual structures, see Type-2 Conditionals and Conditional Chains.
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Open the Italian course →Related Topics
- Congiuntivo Imperfetto: Regular VerbsB1 — How to form the regular congiuntivo imperfetto across all three conjugations — and why this is the tense that finally makes the subjunctive feel natural.
- Congiuntivo Imperfetto: Irregular VerbsB1 — The irregular congiuntivo imperfetto — essere, dare, stare, and the hidden-stem verbs that all reuse the same imperfetto stem.
- Congiuntivo Trapassato: Formation and UsageB1 — The most useful subjunctive tense in everyday Italian — how to form the congiuntivo trapassato and why it lives at the heart of the type-3 counterfactual.
- Sequence of Tenses (Concordanza dei Tempi)B2 — Once the main verb commits to a tense, the congiuntivo in the subordinate clause has only four cells to choose from — laid out by time relation and main-clause tense.
- Type 2 Conditionals: Hypothetical PresentB1 — Type 2 conditionals describe situations that are unreal, contrary to fact, or remotely hypothetical in the present or future. The Italian pattern is se + congiuntivo imperfetto in the if-clause, condizionale presente in the main clause.
- Conditional Chains and Mixed TypesC1 — Stacking conditional logic in Italian — sequenced and interleaved type-1, type-2, and type-3 conditionals, mixed-period counterfactuals (se l'avessi saputo, te lo direi), and the cascade structures Italians use to reason through alternative pasts and presents.