The απαρέμφατο (-ει form)

Every Greek perfect — έχω γράψει, είχα γράψει, θα έχω γράψει — hangs on one small word that never changes: γράψει. Greek grammar calls it the απαρέμφατο (aparémfato), literally "the un-defined form," and it is worth a page of its own because getting it right is 90% of getting the perfect right. Learn how this one form is built and you can build the perfect of any verb in the language.

What it is: one frozen form after έχω

The απαρέμφατο is the invariable form that sits after the auxiliary έχω in the perfect tenses. It always ends in -ει, and — this is the whole point — it is genuinely frozen. It does not agree with the subject, it does not care about tense, it does not inflect for anything. All the grammatical work is done by the auxiliary; the -ει word just names the action.

It comes from the perfective stem + -ει

For a regular verb, the -ει form is built on the perfective stem — the same stem used for the aorist and simple future — with fixed -ει. As a practical regular-verb procedure, take the aorist, remove its augment and personal ending, and add -ει:

Notice the shape: the απαρέμφατο is exactly the 3rd-person singular of the perfective subjunctive (να γράψει, να μιλήσει), just detached from its να and frozen there. That is a genuinely useful shortcut — if you can say να γράψει ("that s/he write"), you already know the perfect form έχω γράψει.

It never inflects — for anything

The Greek form varies lexically from verb to verb (γράψει, δει, πάει), but it never agrees with the subject the way participles do in some languages. Once a verb's -ει form is chosen, that same shape serves all six persons, both numbers, and every gender:

Plural subject, feminine subject, second person — φάει, γυρίσει, πάει never budge. The moment you feel tempted to "make it agree," stop: the -ει form has exactly one shape, forever.

One boundary worth naming, so you know where this page stops: mediopassive verbs build their own απαρέμφατο, on the passive perfective stem and with a stressed -εί — κουράζομαι → έχω κουραστεί, γράφομαι → έχει γραφτεί, πλένομαι → έχω πλυθεί. It is every bit as invariable as the active one; building it is the business of the perfect passive.

The irregular ones — memorize a short list

A handful of very common verbs build a suppletive perfective stem — one that doesn't look like the present at all — and their -ει forms inherit that irregularity. These are the same verbs that are irregular in the aorist, so if you know the aorist you already half-know these. They are short, monosyllabic, and among the most frequent words you will ever use:

Morphologically perfective does not mean "once and sealed"

Greek's -ει form has no imperfective counterpart inside the έχω-perfect: ×έχω γράφει cannot mean "I have been writing." It is morphologically perfective and packages the relevant prior situation as bounded. That package need not contain only one occurrence: Έχω δει αυτό το έργο δύο φορές above is a finite repeated experience, and Έχω δουλέψει πολύ φέτος can summarize an amount of work.

What the construction does not provide is an internal view of one activity still unfolding up to now. For that English "have been doing" meaning, Greek normally uses the plain present with a duration phrase: Γράφω εδώ και δύο ώρες "I've been writing for two hours." Keep the genuine constraint — perfective morphology — without adding an entailment of "once," permanent result, or "done and sealed."

A trap: when the -ει form looks like the present

For a small set of verbs the perfective stem happens to be identical to the present stem, so the -ει form comes out looking exactly like the present 3rd-person singular. The clearest case is κάνω ("do/make"): its -ει form is κάνει, spelled and pronounced the same as κάνει "s/he does." Only the auxiliary tells you which is which — κάνει alone is "s/he does," έχει κάνει is "s/he has done." Do not let the familiar look fool you into dropping the έχω.

Why it looks like an infinitive — because it was one

If the απαρέμφατο feels oddly like an infinitive to you, your instinct is historically correct. Earlier Greek had full infinitival paradigms, while Modern Greek lost the productive infinitive and replaced its ordinary complement uses with να-clauses. The fixed form survives inside compound perfect constructions. That is why it carries no person. But it is not a free modern infinitive: you cannot use γράψει on its own to mean "to write." It occurs with a form of the auxiliary έχω — έχω/είχα/θα έχω γράψει, and also έχοντας γράψει "having written."

Common Mistakes

1. Trying to make the -ει form agree in number. A plural subject does not pluralize the απαρέμφατο; only έχουν changes.

2. Using the imperfective (present) stem instead of the perfective one. The perfect is built on the perfective stem, so γράφω gives γράψει, not ×γράφει.

3. Regularizing a suppletive verb. βλέπω does not give ×βλέψει; its perfective stem is suppletive, so the form is δει.

4. Using the -ει form as a free-standing infinitive. It is not a substitute for "to + verb"; outside the perfect you still need να + a conjugated verb.

Key Takeaways

• The απαρέμφατο is the invariable -ει form that follows έχω/είχα/θα έχω in every perfect tense.
• It is built on the perfective stem + -ει and is identical in shape to the 3sg perfective subjunctive (να γράψει → έχω γράψει).
• It never inflects — same form for every person, number and gender (έχω/έχουμε/είχαν πάει).
• Its perfective morphology packages a bounded prior situation, which may be one occurrence, a finite series, or an amount of activity; it does not inherently mean "once" or "done and sealed."
• The common irregular set is learned alongside the aorists: δει (βλέπω), πει (λέω), φάει (τρώω), πιει (πίνω), βρει (βρίσκω), μπει / βγει, έρθει, πάει.
• It is a remnant of the lost infinitival system — restricted to compound perfect constructions with a form of έχω, never usable freely on its own.