The -αιν- of the present is scaffolding, not part of the word. Take it away and this verb is down to a single consonant — μπ- — which is why its dependent, μπω, is one syllable long and why the whole perfective side looks unrelated to the present. The family it belongs to is worked through on nasal-stem verbs; this card is the inventory.
The paradigm
| Person | Present | Aorist | After θα / να |
|---|---|---|---|
| εγώ | μπαίνω | μπήκα | μπω |
| εσύ | μπαίνεις | μπήκες | μπεις |
| αυτός / αυτή | μπαίνει | μπήκε | μπει |
| εμείς | μπαίνουμε | μπήκαμε | μπούμε |
| εσείς | μπαίνετε | μπήκατε | μπείτε |
| αυτοί | μπαίνουν | μπήκαν | μπουν |
| Slot | Form | Note |
|---|---|---|
| Imperfect | έμπαινα | plural μπαίναμε, μπαίνατε |
| Command | μπες / μπείτε | get in, come in |
| Perfect / pluperfect | έχω / είχα μπει | one -ει form for both |
| Gerund | μπαίνοντας | on the way in |
The stress in μπήκα sits inside the stem rather than on an augment, so unlike έμπαινα it never shifts: μπήκα, μπήκαμε, μπήκατε all keep it on the same vowel.
What μπαίνω does not have
- A passive — does not exist. Dictionaries give μπαίνω no passive, and there is nothing to passivise: you cannot be gone-into. When something is put in rather than going in, Greek changes verb entirely and uses βάζω.
- A -μένος participle — does not exist. No μπαμένος, no μπασμένος (that one belongs to μπάζω, a different verb). For "once inside" use the gerund: μπαίνοντας.
- A direct object — does not exist. μπαίνω never takes a determined accusative the way English enter the room does: no μπήκα το δωμάτιο, no μπήκα την πόρτα. Contrast ανεβαίνω, which does take a real object — ανέβηκα τις σκάλες. The space entered normally goes in σε
- accusative.
Beyond going in
Four senses that no dictionary gloss of "enter" will hand you, and all four are everyday.
Δεν μου μπαίνει το παντελόνι, το έχω να το φορέσω δύο χρόνια.
dhen mu béni to pandelóni, to écho na to foréso dhío chrónia
The trousers don't fit me — I haven't worn them for two years.
Μην πλένεις τα μάλλινα στους εξήντα, γιατί μπαίνουν.
min plénis ta málina stus eksínda, yatí bénun
Don't wash the woollens at sixty degrees, they shrink.
Μισή ώρα εξηγούσα και τελικά μπήκε στο νόημα.
misí óra eksighúsa ke teliká bíke sto nóima
I spent half an hour explaining and eventually the penny dropped.
Μπήκε επιτέλους το ρεύμα στο καινούριο σπίτι.
bíke epitélus to révma sto kenúrio spíti
The electricity has finally been connected at the new place.
A season does the same thing — Μπήκε ο χειμώνας, "winter has set in" — and so does a month, a new year and a working week.
Government
| Frame | Example | Reading |
|---|---|---|
σε
| Μπήκα στο σπίτι. | the space entered — the default |
| bare noun, no article | Μπήκε Ιατρική. | σε drops before an article-less noun |
| σε + abstract noun | Μπήκα σε έξοδα. | land yourself in expense, in trouble |
| reinforcing μέσα | Μπες μέσα. | come on in |
| genitive clitic | Μου μπήκε μια ιδέα. | who it happened to |
| no complement | Μπήκε ο χειμώνας. | a season, a month, the power |
Μπήκα στο σπίτι και κατάλαβα αμέσως ότι κάτι δεν πήγαινε καλά.
bíka sto spíti ke katálava amésos óti káti dhen píyene kalá
I walked into the house and knew straight away that something was wrong.
Μου μπήκε μια ιδέα και δεν μπορώ να τη βγάλω από το μυαλό μου.
mu bíke mia idhéa ke dhen boró na ti vghálo apó to mialó mu
An idea has got into my head and I can't get it out.
A small set of article-less nouns drops the σε in everyday speech, exactly as πάω does: μπήκα σπίτι, μπήκα στρατό, and — the ordinary way to report exam results, in speech and headlines alike — μπήκε Ιατρική, μπήκε Νομική. These are still goals, not objects: the article can never come back. μπήκα Ιατρική and μπήκα στην Ιατρική are both fine; μπήκα την Ιατρική is not.
Ο γιος τους έγραψε πολύ καλά και μπήκε Ιατρική.
o yos tus éghrapse polí kalá ke bíke iatrikí
Their son did really well in the exams and got into Medicine.
For public transport Greek offers a choice that English does not: μπαίνω στο λεωφορείο and ανεβαίνω στο λεωφορείο are both current for getting on a bus or train, with ανεβαίνω felt as the more physical climbing aboard. With a car, μπαίνω. The preposition itself, with its contracted στο / στη / στον, is on σε.
Μπήκαμε στο λεωφορείο την τελευταία στιγμή.
bíkame sto leoforío tin teleftéa stighmí
We got on the bus at the last second.
μπες or μπεις;
Identical in speech, distinct on paper, and both correct in their own slot: μπες is the command, μπεις is the 2nd-person dependent that follows να or θα.
Μπες μέσα, θα κρυώσεις εδώ έξω.
bes mésa, tha kriósis edhó ékso
Come inside, you'll freeze out here.
Θέλω να μπεις μέσα πριν αρχίσει η βροχή.
thélo na bis mésa prin archísi i vrochí
I want you to come in before the rain starts.
Set phrases
| Phrase | Meaning |
|---|---|
| μπαίνω στο νόημα | get it, catch on |
| μπαίνω μέσα (informal) | lose money on it; also: end up in jail |
| μπαίνω στη μέση | get in the way, interfere |
| μπαίνω στη θέση σου | put myself in your shoes |
| μπαίνω σε έξοδα | go to expense |
| μπήκε ο χειμώνας | winter has set in |
| δεν μου μπαίνει | it doesn't fit me |
| μπήκα πρώτος | I got in first — of university entrance |
Μπήκα μέσα δύο χιλιάδες ευρώ φέτος.
bíka mésa dhío chiliádhes evró fétos
I was two thousand euros down this year. (informal)
Key Takeaways
- μπαίνω · έμπαινα · μπήκα · να μπω · μπες / μπείτε · έχω μπει · μπαίνοντας.
- The dependent is one syllable — μπω, μπεις, μπει take no tonos; μπούμε, μπείτε do.
- No passive, no -μένος participle, no direct object. The space entered takes σε
- accusative — dropped only before a bare noun (μπήκα σπίτι, μπήκε Ιατρική), never with the article back on.
- Beyond entering: clothes that fit (δεν μου μπαίνει), wool that shrinks (μπαίνουν), a point you finally get (μπήκα στο νόημα), a season or a utility that starts (μπήκε ο χειμώνας, μπήκε το ρεύμα).
- μπες commands, μπεις follows να and θα — same sound, different spelling.
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Start learning Greek →Related Topics
- βγαίνω (to go out/exit)A2 — βγαίνω is only nominally 'exit' — one small paradigm covers going out for the evening, dating someone, results being published, a sum adding up, a colour running and retiring. Card lists the paradigm, the από/σε/με frames, the idiom cluster, and the forms this verb does not have.
- βάζω (to put)A2 — The -ζω verb that escapes the -ζω aorist split: not έβαξα, not έβασα, but έβαλα from a λ-final root. Full forms, the eight English verbs βάζω has swallowed (put, pour, turn on, enrol), the βάζω τα κλάματα frame, and why βάλθηκα is not a passive.
- Nasal-Stem Verbs (μπαίνω, πίνω)B1 — In μαθαίνω, καταλαβαίνω, μπαίνω, πίνω and δίνω the -ν- or -αιν- belongs to the imperfective half of the verb only — it is there in μαθαίνω and μάθαινα alike, and gone from everything perfective. Drop it and the bare root underneath is the perfective stem (μάθ-, καταλάβ-, μπ-, πι-). Covers the whole family, the -ηκα aorists that look passive and are not, the causative partners in -άζω, and μαθαίνω's double life as both 'learn' and 'teach'.