Pensi is the regular verb for thinking, directing the mind toward a topic, and presenting a belief or judgment. Its complement reveals the viewpoint: pensi pri io names what occupies the mind, while pensi, ke... states the proposition held in thought. English “think of/about/that” does not map word for word onto a single Esperanto frame.
Complete regular paradigm
| Form | Function | Typical translation |
|---|---|---|
| pensi | infinitive | to think |
| pensas | present indicative | think(s), is thinking |
| pensis | past indicative | thought |
| pensos | future indicative | will think |
| pensus | conditional | would think |
| pensu | volitive | think!, consider!, let ... think |
The same finite form serves every subject: mi pensas, ŝi pensas, ili pensas. Pensus presents a hypothetical thought or expected judgment; pensu asks someone to engage in thought.
Mi pensas pri la plej simpla maniero klarigi la problemon.
I'm thinking about the simplest way to explain the problem.
Kion vi pensus, se la prezo subite duobliĝus?
What would you think if the price suddenly doubled?
Pensu antaŭ ol vi sendos mesaĝon, kiun vi poste bedaŭros.
Think before you send a message that you'll later regret.
Pensi pri: a topic occupying the mind
Use pri to introduce the subject matter of thought. The phrase answers Pri kio? “About what?”
Dum la tuta vojaĝo ŝi pensis pri sia venonta intervjuo.
Throughout the journey she thought about her upcoming interview.
Mi ofte pensas pri la homoj, kiuj helpis min komence.
I often think of the people who helped me at the beginning.
English alternates “think about” and “think of” with subtle differences. Esperanto normally uses pri for both when the meaning is mental attention to a topic or person. De does not fill this role.
— Pri kio vi pensas? — Pri tio, ĉu ni havos sufiĉe da tempo.
— What are you thinking about? — About whether we'll have enough time.
The complement of pri can be a noun phrase, pronoun, or tio followed by an explanatory clause. Pri tio, ĉu... is useful when the topic itself is an unresolved yes-or-no question.
Pensi, ke...: a proposition or opinion
A ke-clause supplies the content regarded as true, likely, or reasonable.
Mi pensas, ke la lasta trajno foriras je la dekunua, sed ni kontrolu la horaron.
I think the last train leaves at eleven, but let's check the timetable.
La kuracisto pensis, ke la doloro malaperos post kelkaj tagoj.
The doctor thought the pain would disappear after a few days.
The clause is the object-like content of pensi. Esperanto does not require tense backshift after past pensis: the embedded tense states the time actually meant. Pensis, ke la doloro malaperos views the disappearance as later than the past thinking; pensis, ke la doloro malaperis places it earlier.
Mi ne pensas, ke pli longa kunveno solvos la problemon.
I don't think a longer meeting will solve the problem.
The negative naturally belongs to the main verb in this common pattern. Mi pensas, ke ... ne ... instead directly negates the embedded event and may create a different focus.
An unresolved question is not a settled ke-proposition. It can instead become the topic of thought through pri tio followed by an interrogative clause:
Mi pensis pri tio, kial la ĉambro estis tiel malvarma, kaj poste mi rimarkis la malfermitan fenestron.
I was thinking about why the room was so cold, and then I noticed the open window.
Pripensi kial... is a more compact alternative when sustained consideration is emphasized.
Asking for an opinion
Kion vi pensas pri...? combines two roles: kion asks for the content of the person's thought, and the pri-phrase names its topic.
Kion vi pensas pri la propono kunigi la du teamojn?
What do you think about the proposal to merge the two teams?
Mi pensas, ke ĝi ŝparus tempon, sed la respondecoj devus esti pli klare dividitaj.
I think it would save time, but the responsibilities would need to be divided more clearly.
Opinii is close but more specifically means hold or express an evaluation. Pensi is broader: it can describe an ongoing mental process, recollection, planning, inference, or opinion. In a survey or debate, Kion vi opinias pri...? explicitly requests an assessment; in conversation, Kion vi pensas pri...? is completely neutral.
Kredi, ke... often conveys belief with less emphasis on reasoning, while supozi, ke... marks an assumption. These boundaries overlap; the speaker chooses the mental stance to foreground.
Pripensi, elpensi, and other derivatives
Prefixes make the structure or result of thought more specific:
- pripensi — consider carefully, think over;
- elpensi — devise, invent, think up;
- ekpensi — begin or suddenly happen to think;
- trapensi — think through thoroughly;
- repensi — think again, rethink;
- pensado — the activity or process of thinking;
- pensmaniero — way of thinking, mindset.
Pripensi is an established Fundamental compound and normally takes a direct object: pripensi proponon. It can also take an infinitive naming a possible action.
Ni pripensas translokiĝi al pli malgranda oficejo post la somero.
We're considering moving to a smaller office after the summer.
La inĝenieroj elpensis malmultekostan manieron reuzi la varmon.
The engineers devised an inexpensive way to reuse the heat.
Post la dua averto li repensis sian decidon veturi tra la ŝtormo.
After the second warning, he reconsidered his decision to drive through the storm.
English “think up” therefore usually calls for elpensi, not a literal combination involving “up.” Pripensi profiles careful consideration, not merely having a topic in mind.
Participles and their actual use
| Time relation | Active | Passive |
|---|---|---|
| ongoing | pensanta — thinking | pensata — being thought |
| earlier/completed | pensinta — having thought | pensita — thought, conceived |
| later/intended | pensonta — about to think | pensota — to be thought |
All six forms are regular, but the passive forms of bare pensi are less frequent because topics normally appear with pri and propositions as clauses. Passive participles of object-taking derivatives are more useful: zorge pripensita propono, lerte elpensita solvo.
Poste, pensante pri la interparolo, mi komprenis kial ŝi hezitis.
Later, thinking about the conversation, I understood why she hesitated.
La plano estas bone pripensita, sed ĝia efektivigo estos multekosta.
The plan is well thought out, but implementing it will be expensive.
This frequency difference is lexical, not an irregularity in the participle system.
Frequency, register, and status
Pensi is extremely frequent and neutral in conversation and writing. Pripensi and elpensi are also neutral; pensmaniero occurs often in reflective, political, and (academic) prose. Foundational norm: pens-, pripensi, the verb endings, and pri are all Fundamental. Accepted variation: pensi, ke... and opinii, ke... can overlap when an opinion is stated, but they foreground different mental stances. Pedagogical recommendation: use pri for a topic and ke for a proposition. Attested usage: both frames and the major compounds are widespread across Tekstaro genres.
See Ke-Clauses for clause roles and tense choice.
Common Mistakes
Using de for the topic
❌ Mi ofte pensas de mia familio, kiam mi vojaĝas.
Incorrect — the topic of thought is introduced by pri.
✅ Mi ofte pensas pri mia familio, kiam mi vojaĝas.
I often think of my family when I travel.
Omitting ke before a complete proposition
❌ Mi pensas la nova plano estas tro komplika.
Incorrect — a complete proposition requires the clause introducer ke.
✅ Mi pensas, ke la nova plano estas tro komplika.
I think the new plan is too complicated.
Treating the topic as a direct object
❌ Mi pensis la problemon dum la tuta nokto.
Incorrect for 'thought about the problem' — bare pensi uses pri for its topic.
✅ Mi pensis pri la problemo dum la tuta nokto.
I thought about the problem all night.
Adding pri after object-taking pripensi
❌ Ni pripensas pri la nova propono.
Incorrect — pripensi takes the matter considered as a direct object.
✅ Ni pripensas la novan proponon.
We're considering the new proposal.
Key Takeaways
- Pensi is regular; use pensi pri for a topic and pensi, ke... for propositional content.
- Kion vi pensas pri...? is the neutral way to ask someone's view on a topic.
- Pripensi means consider carefully; elpensi means devise or think up.
- Bare passive participles exist regularly but are less frequent than participles of object-taking compounds.
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Start learning Esperanto →Related Topics
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