Tænke means to think in the sense of mental activity — to ponder, to use your head, to have thoughts going through your mind. What it does not mean is "to hold an opinion." English uses "think" for both ("I'm thinking about it" and "I think it's good"), but Danish splits these across three verbs: tænke (think = process thoughts), tro (think = believe / suppose), and synes (think = find / have the personal opinion that). Mastering this trio is one of the genuine milestones of early Danish, and tænke is the piece English speakers most often overuse.
Principal parts
Tænke is a regular weak verb of the -te class, with a predictable stem-consonant adjustment (the k surfaces before the -te).
| Infinitive | Present | Past | Past participle | Imperative |
|---|---|---|---|---|
| (at) tænke | tænker | tænkte | tænkt | tænk! |
The past tænkte and participle tænkt keep the k from the stem. The imperative tænk! on its own is a common exclamation meaning "imagine!" or "just think!"
Present: tænker — the mental activity
Use tænker for the act of thinking itself — what is going through your mind.
Lad mig lige tænke.
Let me just think for a second.
Hvad tænker du på?
What are you thinking about?
Jeg kan ikke tænke klart, før jeg har fået kaffe.
I can't think clearly until I've had coffee.
tænke på — to think of / about
The most common pattern is tænke på — to think of or about someone or something. This is affectionate, ruminative thinking, not forming an opinion.
Jeg tænker på dig.
I'm thinking of you.
Hun tænker meget på sin fremtid for tiden.
She's thinking a lot about her future these days.
tænke over — to think over / consider
Tænke over means to reflect on or mull over a question before deciding.
Jeg skal lige tænke over det.
I just need to think it over.
Har du tænkt over mit forslag?
Have you thought about my proposal?
Past: tænkte
Jeg tænkte på dig hele dagen i går.
I thought about you all day yesterday.
Vi tænkte aldrig over, hvor heldige vi var.
We never thought about how lucky we were.
Present perfect: har tænkt
Jeg har tænkt over det, og jeg siger ja.
I've thought it over, and I'll say yes.
Har du nogensinde tænkt på at flytte til udlandet?
Have you ever thought about moving abroad?
The think-trio: tænke vs tro vs synes
This is the heart of the matter. English "I think..." maps onto three different Danish verbs depending on what you mean:
| Verb | Sense of "think" | Example |
|---|---|---|
| tænke | process thoughts; ponder (a mental activity) | Jeg tænker på det. — I'm thinking about it. |
| tro | believe / suppose (think something is factually so, but you're not sure) | Jeg tror, det regner i morgen. — I think it'll rain tomorrow. |
| synes | find / have the personal opinion that (a matter of taste or judgement) | Jeg synes, filmen er god. — I think the film is good. |
The rule of thumb: if you could replace "think" with "in my opinion / I find," use synes. If you could replace it with "I believe / I suppose / I reckon," use tro. Only if you literally mean the act of thinking — what is in your head — use tænke. For the full treatment, see synes, tro and tænke.
Jeg synes, det er en god idé, men jeg tror ikke, vi har tid. Jeg tænker stadig over det.
I think (find) it's a good idea, but I don't think (believe) we have time. I'm still thinking it over.
That one sentence uses all three verbs correctly — a perfect illustration of why English speakers need to slow down on "think."
A short dialogue
— Du ser tankefuld ud. Hvad tænker du på? — Jeg tænker på, om jeg skal sige ja til det nye job. — Hvad synes du selv? — Jeg synes, det lyder spændende, men jeg tror, det bliver hårdt. Jeg må lige tænke lidt mere over det.
— You look thoughtful. What are you thinking about? — I'm thinking about whether to take the new job. — What do you think yourself? — I think it sounds exciting, but I reckon it'll be tough. I just need to think it over a bit more.
Common mistakes
❌ Jeg tænker, det er godt.
Wrong: this is an opinion, so tænke is the wrong verb.
✅ Jeg synes, det er godt.
Correct: synes for a personal opinion/judgement.
❌ Jeg tænker, det regner i morgen.
Wrong: this is a guess about a fact, not a mental activity.
✅ Jeg tror, det regner i morgen.
Correct: tro for 'I believe/suppose.'
❌ Jeg tænker dig.
Wrong: tænke needs the preposition på to mean 'think of.'
✅ Jeg tænker på dig.
Correct: tænke på = to think of/about.
❌ Jeg tænkede over det hele natten.
Wrong: tænke is a -te verb, not a -ede verb.
✅ Jeg tænkte over det hele natten.
Correct: tænk + te = tænkte.
❌ Har du tænket over det?
Wrong participle: -te verbs take -t, not -et.
✅ Har du tænkt over det?
Correct: the participle is tænkt.
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.
- TroA2 — Full reference for tro — to believe, to think, to suppose — and how it fits into the Danish three-way think split with synes and tænke.
- 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.
- The Present TenseA1 — How to form the Danish present (add -r) and why one present form covers English's simple present, present continuous, and 'going to' future.
- Weak Past: The -te ClassA2 — The second weak class of Danish verbs — past in -te, participle in -t — and how to tell it apart from the larger -ede class.