Tro is the Danish verb for believing and for thinking in the sense of supposing, reckoning, or guessing. It expresses something you hold to be true without being certain — "I think it'll rain," "I believe she's at home." This makes it one third of a famous trap for English speakers: Danish splits the single English verb "think" across three verbs — tro, synes, and tænke — and choosing the right one is one of the defining skills of sounding Danish.
Principal parts
| Form | Danish | English |
|---|---|---|
| Infinitive | (at) tro | to believe, to think |
| Present | tror | believe(s), think(s) |
| Past | troede | believed, thought |
| Past participle | troet | believed, thought |
| Imperative | tro! | believe! |
Tro is a regular weak verb of the -ede class. Because the stem ends in a vowel (tro-), the present simply adds -r to give tror, and the past adds -ede to give troede (the e of the ending sits next to the stem vowel — both letters are written and the word is two syllables). The participle is troet.
Present tense
The present tror is extremely common as a way of softening a statement — flagging it as your guess rather than a fact.
Jeg tror, det bliver regn i morgen.
I think it's going to rain tomorrow.
Tror du på spøgelser?
Do you believe in ghosts?
Hun tror, at toget er forsinket.
She thinks the train is delayed.
Notice that Danish puts a comma before the subordinate clause (Jeg tror, det...) where English does not. The little word at ("that") is optional in such clauses, just as "that" is optional in English.
Past tense
The simple past troede often carries the implication that the belief turned out to be wrong — "I thought (but I was mistaken)."
Jeg troede, du var taget hjem.
I thought you'd gone home.
Vi troede på ham, men han løj.
We believed him, but he lied.
Present perfect
Tro takes the auxiliary har in the perfect; the participle is troet.
Det har jeg aldrig troet på.
I've never believed in that.
Har du virkelig troet på den historie?
Have you really believed that story?
Common collocations
| Phrase | Meaning |
|---|---|
| tro på (noget / nogen) | to believe in (something / someone) |
| tro at ... | to think / suppose that ... |
| tro det eller ej | believe it or not |
| tro mig | believe me, trust me |
| jeg tror det ikke | I don't think so |
Tro mig, det er en god idé.
Believe me, it's a good idea.
Tror du, vi når det?
Do you think we'll make it?
A natural dialogue
— Tror du, hun kommer? — Det tror jeg ikke, hun har for travlt.
— Do you think she'll come? — I don't think so, she's too busy.
The big one: tro vs. synes vs. tænke
English uses "think" for three different mental operations. Danish keeps them apart, and using the wrong one is the single most recognisable mistake an English speaker makes.
| Verb | Core meaning | Use it when ... |
|---|---|---|
| tro | believe, suppose, guess | you're stating a belief you can't be sure of — a prediction or assumption about facts |
| synes | find, be of the opinion | you're giving a personal opinion or evaluation based on your own taste or experience |
| tænke | think, use one's mind | you mean the mental activity itself — pondering, having something on your mind |
The test: if you could replace "think" with "believe/suppose," use tro. If you could replace it with "find" or "in my opinion," use synes. If you mean the act of cogitating, use tænke.
- Jeg *tror, filmen er god* = I think (= I suppose) the film is good — maybe I haven't seen it; I'm guessing.
- Jeg *synes, filmen er god* = I think (= I find) the film good — I've seen it; it's my opinion.
- Jeg *tænker på filmen* = I'm thinking about the film — it's on my mind.
Jeg synes, maden var lækker.
I think (= I found) the food was delicious.
Jeg tror, maden er god her, men jeg har ikke prøvet det.
I think (= I'd guess) the food is good here, but I haven't tried it.
Common mistakes
❌ Jeg tænker, det er en god film.
Wrong — for a guess/belief about a fact, Danish uses tro, not tænke.
✅ Jeg tror, det er en god film.
I think (suppose) it's a good film.
❌ Jeg tror, kjolen er flot på dig.
Wrong — this is a personal opinion/evaluation, so use synes.
✅ Jeg synes, kjolen er flot på dig.
I think (find) the dress looks great on you.
❌ Jeg tror i Gud.
Wrong preposition — you tro PÅ (believe IN) something.
✅ Jeg tror på Gud.
I believe in God.
❌ Jeg har troede på det.
Wrong — after har use the participle troet, not the past tense troede.
✅ Jeg har troet på det.
I have believed in it.
❌ Jeg tror så.
Wrong — there is no 'jeg tror så' for 'I think so'; Danish fronts the object instead.
✅ Det tror jeg / Det tror jeg ikke.
I think so / I don't think so.
Key takeaways
- Tro is a regular -ede verb with a vowel stem: tror / troede / troet, perfect with har.
- It means believe / suppose / guess — an uncertain belief, not a settled opinion.
- You tro på something (believe in).
- Keep the trio straight: tro = suppose/believe, synes = find/opine, tænke = use the mind.
Now practice Danish
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Start learning Danish→Related Topics
- Synes, Tro, Tænke: Three Ways to ThinkB1 — How to choose between synes (opinion), tro (belief/guess) and tænke (the mental activity) — Danish splits English 'think' three ways.
- SynesB2 — Full reference for the deponent -s verb synes ('to think / find / seem'), the synes/syntes spelling trap, and how it differs from tro, mene and tænke.
- TænkeA2 — How to use the Danish verb tænke (to think — the mental activity) — conjugation, tænke på/over, and the tænke/tro/synes split.
- MeneA2 — How to use mene (to mean, to be of the opinion) — its forms and the crucial split between mene, betyde, synes and tro.
- Weak Past: The -ede ClassA1 — The largest, productive class of Danish regular verbs — past in -ede, participle in -et — and the safe default for any verb you don't recognise.