When you conjugate the verb a citi (to read), something unexpected appears between the stem and the ending: citesc, citești, citește — a chunk -esc- that wasn't in the infinitive. This is the -esc / -ăsc infix, and it is the single most common pattern in Class IV (the -i verbs). It shows up in four of the six persons and vanishes in the other two. Understanding where it sits and where it drops is the key to conjugating a huge slice of everyday Romanian, because most -i verbs — and a few -a verbs — use it.
Where the infix sits
The infix is inserted in the singular (eu, tu, el/ea) and in the third-person plural (ei/ele). It is absent from noi and voi. Here is the model verb a citi laid out so the pattern is unmistakable.
| Person | Form | Infix? |
|---|---|---|
| eu | citesc | yes (-esc) |
| tu | citești | yes (-eșt-) |
| el / ea | citește | yes (-eșt-) |
| noi | citim | no — plain stem + -im |
| voi | citiți | no — plain stem + -iți |
| ei / ele | citesc | yes (-esc) |
Citesc o carte despre istoria Bucureștiului.
I'm reading a book about the history of Bucharest.
Citești prea repede și pierzi detaliile.
You read too fast and miss the details.
Citim împreună în fiecare seară.
We read together every evening. (no infix — citim)
The verb a vorbi (to speak) works identically — and is so frequent it's worth knowing cold:
Vorbesc românește acasă și engleză la birou.
I speak Romanian at home and English at the office.
Vorbește mai rar, te rog.
Speak more slowly, please.
Vorbim despre asta mâine.
We'll talk about it tomorrow. (no infix — vorbim)
The back-vowel variant: -ăsc
After certain stems — chiefly verbs whose infinitive ends in -î — the infix surfaces with a back vowel as -ăsc / -ășt- instead of -esc / -eșt-. The distribution is set by the stem's vowel harmony, not by choice. The two clearest everyday examples are a hotărî (to decide) and a urî (to hate).
| Person | a hotărî | a urî |
|---|---|---|
| eu | hotărăsc | urăsc |
| tu | hotărăști | urăști |
| el / ea | hotărăște | urăște |
| noi | hotărâm | urâm |
| voi | hotărâți | urâți |
| ei / ele | hotărăsc | urăsc |
Hotărăsc singur ce e mai bine pentru mine.
I decide for myself what's best for me.
Urăște să fie întrerupt.
He hates being interrupted.
Hotărâm împreună unde mergem în vacanță.
We decide together where we go on holiday. (no infix — hotărâm)
Notice the same on/off pattern: the infix is -ăsc / -ășt- in the four outer persons and gone in noi / voi, where the bare -â stem returns (hotărâm, urâm).
Which verbs take it? There is no airtight rule
Here is the honest part. You cannot look at a Class IV infinitive and be certain whether it takes the infix. A dormi (to sleep) does not — dorm, dormi, doarme. A citi does — citesc, citești, citește. There is no spelling clue that reliably separates them, so the infix must be learned per verb.
That said, there is a strong tendency you can lean on: most abstract, derived, and borrowed -i verbs take the infix. Verbs built from nouns or adjectives, and the steady stream of internationalisms entering Romanian, default to -esc.
| Verb | 1sg | Type |
|---|---|---|
| a defini (to define) | definesc | borrowed/abstract — infix |
| a folosi (to use) | folosesc | derived — infix |
| a iubi (to love) | iubesc | infix |
| a dormi (to sleep) | dorm | basic/concrete — NO infix |
| a fugi (to run/flee) | fug | NO infix |
| a simți (to feel) | simt | NO infix |
Folosesc aplicația asta în fiecare zi.
I use this app every day. (folosesc — infix)
Dorm prost când e prea cald.
I sleep badly when it's too hot. (dorm — no infix)
A Latin fossil, and the reason it matters
The infix is not a Romanian invention. It descends from the Latin inchoative suffix -sc- (as in crescere "to grow," florescere "to begin to flower"), which originally marked the beginning of an action. Over time the "beginning" meaning faded and the suffix simply became a conjugation marker — and Romanian, like Italian (finisco, finisci) and French (finis, finissons), generalized it across a large class of verbs. The practical upshot is the point most courses bury: because the -esc class is the single biggest sub-pattern in Class IV, the smart default for a learner is to expect the infix and treat the plain verbs as the marked exceptions to memorize.
The classic error: keeping the infix in 'we' and 'you'
The infix's on/off behaviour trips up nearly everyone. Once you've drilled citesc, citești, citește, the hand wants to keep going with citescem or citescim — but the infix drops in noi and voi. The 1pl/2pl forms are built on the bare stem: citim, citiți.
❌ Noi citescim cartea împreună.
Incorrect — the infix drops in 1pl; the form is 'citim'.
✅ Noi citim cartea împreună.
We read the book together.
Common Mistakes
❌ Noi vorbescem două limbi.
Incorrect — no infix in 1pl: 'vorbim'.
✅ Noi vorbim două limbi.
We speak two languages.
❌ Voi folosesciți programul ăsta?
Incorrect — no infix in 2pl: 'folosiți'.
✅ Voi folosiți programul ăsta?
Do you (all) use this program?
❌ Eu dormesc opt ore pe noapte.
Incorrect — 'a dormi' takes no infix: 'dorm'.
✅ Eu dorm opt ore pe noapte.
I sleep eight hours a night.
❌ Eu hotăresc singur.
Incorrect — this stem uses the back-vowel variant: 'hotărăsc'.
✅ Eu hotărăsc singur.
I decide for myself.
❌ Eu citi o carte acum.
Incorrect — the present needs the infix: 'citesc'; 'a citi' is the infinitive.
✅ Eu citesc o carte acum.
I'm reading a book right now.
Key Takeaways
- The -esc / -ăsc infix appears in eu, tu, el/ea, ei/ele and drops in noi, voi.
- The back-vowel form -ăsc appears after certain stems (notably -î verbs: hotărăsc, urăsc).
- There's no fully reliable rule for which -i verbs take it — learn it per verb — but abstract/borrowed verbs almost always do (definesc, folosesc).
- The plain (no-infix) verbs are a smaller, basic set (dorm, fug, simt, vin, țin).
- It descends from the Latin inchoative -sc-; because it's the biggest Class IV pattern, default to expecting it.
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Start learning Romanian→Related Topics
- Class IV Present: -esc VerbsA2 — How to conjugate the dominant Class IV subtype that inserts -esc (or back-vowel -ăsc) in the singular and third-person plural — the single most common present-tense pattern in Romanian.
- Class IV Present: Plain -i VerbsA2 — How to conjugate the closed set of common Class IV (-i) verbs that take no -esc infix, including a dormi, a veni, and a simți, with their o → oa diphthongization.
- The Four Conjugation ClassesA2 — How Romanian sorts verbs into four classes by infinitive ending, why class membership predicts the present tense, and the all-important -esc/-ăsc sub-pattern of class IV.
- Class I Present: The -ez InfixA2 — How to conjugate the very common Class I subtype that inserts -ez in the singular and third-person plural, the default pattern for modern -a verbs and loanwords.
- Stem Alternations: An OverviewB1 — The predictable vowel and consonant alternations that reshape Romanian verb stems across the paradigm — and why learning them once pays off across the whole grammar.