Use the accusative -n when an Esperanto verb takes a direct object. Use a preposition when Esperanto presents the participant through a relation such as recipient, topic, source, instrument, location, or cause. The choice belongs to the Esperanto construction—not to the presence or absence of to, for, about, or another preposition in an English translation.
The quick decision
Ask these questions in order:
- What is the main verb, in this exact meaning?
- Does that Esperanto verb select the participant directly as its object? Use -n.
- Does the participant instead have a named relation—al a recipient, pri a topic, de/el a source, per an instrument, pro a cause? Use that preposition.
- If a preposition is already present, do not add object -n. Directional -n after a spatial preposition is a separate rule.
- If the verb has two established frames, learn their meanings and distribution rather than inventing a free alternation.
The deeper principle is valency: a verb organizes its participants. See verb–preposition frames for the broader system.
Use -n for the verb's direct object
The object is the participant that the Esperanto verb selects directly. It need not be physically changed.
Mi aŭskultis la intervjuon dum mi kuiris.
I listened to the interview while I cooked.
English says listen to, but Esperanto aŭskulti takes the perceived sound or content as an object: la intervjuon.
Ni serĉas pli trankvilan apartamenton proksime al la universitato.
We are looking for a quieter apartment near the university.
English inserts for; Esperanto serĉi directly selects what is sought.
Ĉu vi jam dankis Aminan pro ŝia helpo?
Have you already thanked Amina for her help?
This sentence shows two different roles. Aminan is the person directly thanked and takes -n. Pro ŝia helpo states the reason for the thanks and uses pro.
This is also why transitivity cannot be predicted from real-world affectedness. A message is not physically changed when you read it, yet legi mesaĝon has an object. A colleague may benefit greatly when you reply, yet respondi al kolego uses al. “Affected thing” can be a useful clue, but the lexical frame of the Esperanto verb is decisive.
Use a preposition for a relational complement
A preposition explicitly names how a participant connects to the event. With respondi, the addressee is a target marked by al; with pensi, the subject matter is a topic marked by pri.
Mi respondos al via mesaĝo post la kunveno.
I will reply to your message after the meeting.
Ŝi ofte pensas pri sia unua vojaĝo eksterlanden.
She often thinks about her first trip abroad.
La raporto konsistas el tri mallongaj partoj.
The report consists of three short parts.
Al, pri, and el are not decorative translations of English short words. They define target, topic, and composition/source. Their noun phrases do not take ordinary accusative marking.
— Al kiu vi sendis la fakturon? — Al la nova librotenisto.
— To whom did you send the invoice? — To the new accountant.
The thing sent is the object (la fakturon); the recipient is an al complement. The question preserves the same role marker: al kiu, not kiun.
Contrast the same scene with different verbs
Similar real-world situations can receive different grammar because the verbs frame them differently.
Ni diskutis la buĝeton dum preskaŭ horo.
We discussed the budget for almost an hour.
Ni parolis pri la buĝeto dum preskaŭ horo.
We talked about the budget for almost an hour.
Diskuti can select the issue directly as an object; paroli presents it as a topic with pri. The English translations both contain a topic, but the Esperanto verb decides its syntax.
Mi demandis la organizanton pri la komenca horo.
I asked the organizer about the starting time.
Here la organizanton is the person questioned, while pri la komenca horo is the subject matter. If you want to request an action rather than information, choose another construction:
Mi petis la organizanton sendi la programon.
I asked the organizer to send the program.
Changing only a preposition would leave the English-based analysis intact. The complete repair selects demandi for a question and peti for a request, then builds the corresponding frame.
Do not use -n after an ordinary preposition
The preposition already marks the noun phrase's role. An object inside that phrase may still have agreement of number, but not object -n.
Ŝi vojaĝis kun du proksimaj amikoj.
She travelled with two close friends.
Ni parolis pri la novaj reguloj, ne pri la malnova propono.
We talked about the new rules, not about the old proposal.
The adjectives agree in number where necessary, but kun and pri block ordinary object marking. Compare a genuine object:
Ni zorge legis la novajn regulojn antaŭ la kunsido.
We carefully read the new rules before the meeting.
Now la novajn regulojn is directly selected by legis, so the noun and adjective take -n.
Spatial expressions with directional -n, such as en la ĉambron, are not exceptions that turn the phrase into an object. The -n marks a destination inside the room; the separate directional versus static guide explains that contrast.
Remember that -n has non-object jobs
Not every accusative-looking phrase is an object. -n can also mark duration, a time point, measure, or direction.
Ni atendis kvardek minutojn antaŭ ol la pordoj malfermiĝis.
We waited forty minutes before the doors opened.
Kvardek minutojn measures the duration; it is not something waited for. A sentence can contain both an object and a measure:
Ni atendis la kurieron kvardek minutojn.
We waited for the courier for forty minutes.
La kurieron is the object of atendis; kvardek minutojn is a duration. The ending alone does not identify the semantic role—meaning and the verb frame do.
Genuine overlap is lexical, not unlimited
Some verbs conventionally permit more than one frame. Helpi iun and helpi al iu are both foundationally supported and accepted.
La volontuloj helpis nin aranĝi la seĝojn.
The volunteers helped us arrange the chairs.
La volontuloj helpis al ni per klaraj instrukcioj.
The volunteers helped us with clear instructions.
The object frame is compact and common; al explicitly presents the helped person as a beneficiary. This established pair does not mean every object can be replaced by al. Corpus evidence can compare the distribution of recognized alternatives, but a few calqued examples do not create a general rule.
The foundational norm establishes object -n and prepositional role marking. Detailed grammar and good dictionaries specify individual verb frames. For learners, the safest recommendation is to master one neutral frame per sense, then add documented alternatives.
One clause may contain several different roles
A longer sentence can have a direct object and several prepositional complements at once. Give each phrase its own analysis instead of choosing one marking rule for the whole sentence.
La redaktoro sendis la korektitan artikolon al la aŭtoro per retpoŝto.
The editor sent the corrected article to the author by email.
La korektitan artikolon is what was sent, so it is the object. Al la aŭtoro names the recipient, and per retpoŝto names the means. English happens to use comparable phrases here, but that agreement is not guaranteed with another verb.
Ŝi informis la teamon pri la prokrasto post la kunveno.
She informed the team about the delay after the meeting.
The people informed form the object la teamon; the information topic follows pri. Notice that Esperanto does not copy the English frame inform the team of the delay mechanically. Once the main verb is chosen, assign each participant the role required by its Esperanto frame.
Decision table
| Question | Choice | Model |
|---|---|---|
| Does this verb directly select the participant? | accusative object | serĉi laboron |
| Is it a recipient or target? | al | respondi al kolego |
| Is it a topic? | pri | paroli pri plano |
| Is it a source or origin? | de/el, according to meaning | ricevi de ŝi; eliri el domo |
| Is it an instrument? | per | tranĉi per tranĉilo |
| Is -n measuring time/extent? | non-object accusative | atendi horon |
Common Mistakes
Copying English listen to
❌ Mi aŭskultis al la nova podkasto.
Incorrect — standard aŭskulti takes the heard content as a direct object.
✅ Mi aŭskultis la novan podkaston.
I listened to the new podcast.
Adding -n after a preposition
❌ Ni parolis pri la novan horaron.
Incorrect — pri already marks the role.
✅ Ni parolis pri la nova horaro.
We talked about the new schedule.
Omitting -n after deleting an English preposition
❌ Ŝi serĉas nova laboro.
Incorrect — nova laboro is the object of serĉas.
✅ Ŝi serĉas novan laboron.
She is looking for a new job.
Treating every -n phrase as an object
❌ En «Mi kuris kvin kilometrojn», kvin kilometrojn estas la objekto de kuris.
Incorrect analysis — the phrase measures distance.
✅ En «Mi kuris kvin kilometrojn», la akuzativa esprimo montras distancon.
In ‘I ran five kilometers,’ the accusative expression shows distance.
Key Takeaways
Choose from the Esperanto frame: direct object -n for a participant selected by the verb, or a preposition for an explicit semantic relation. Do not translate English prepositions mechanically, do not add object -n after an ordinary preposition, and do not assume every -n phrase is an object.
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Start learning Esperanto →Related Topics
- Direct ObjectsA1 — Learn which Esperanto verb complements are direct objects, how -n marks them, and how object marking remains stable when word order changes.
- No Accusative after Ordinary PrepositionsA1 — Learn why ordinary Esperanto prepositions take unmarked complements and how to distinguish them from directional and exceptional combinations with -n.
- Verb-Preposition FramesB1 — Learn which Esperanto verbs take direct objects and which select al, pri, de, kun, or je—and how the frame changes meaning.
- English Prepositions in Esperanto FramesA2 — Choose Esperanto objects and prepositions from each word's meaning and valency instead of translating English prepositions one by one.
- AlA2 — Use al for movement toward a goal, recipients, orientation, and abstract targets without adding an unnecessary accusative ending.
- PriB2 — Use pri to mark a topic, concern, or matter that an action, text, thought, or relationship is about.