düşünmek ("to think, to consider, to reflect on") is the verb behind almost everything you say about your own mind: "I'm thinking about you," "I think that you're right," "let me think." English uses one verb "think" for two quite different jobs — thinking about something and thinking that something is true — and Turkish handles each with a different structure. düşünmek takes a plain accusative object for "think about," and a nominalized -DIK clause for "think that…". It is also a productive root, giving you the everyday noun düşünce ("thought, idea") and the converb düşünerek ("thoughtfully, while thinking").
"Think about": the accusative object
When you have someone or something in mind — you are turning them over in your thoughts — düşünmek takes a direct object in the accusative (-(y)I). Where English inserts "about," Turkish needs no preposition at all; the accusative does the work.
Bütün gün seni düşünüyorum, aklımdan çıkmıyorsun.
I'm thinking about you all day, I can't get you out of my mind.
Tatil planını düşünüyoruz, belki Karadeniz'e gideriz.
We're thinking about the holiday plan, maybe we'll go to the Black Sea.
Annemi düşününce içim acıyor, çok özledim.
When I think of my mother my heart aches, I miss her so much.
This is a clean win over English: there is no separate word for "about." Seni düşünüyorum is "I'm thinking about you" with the accusative -i on sen carrying the entire "about" relationship. The verb can also be used absolutely — düşünüyorum on its own means "I'm thinking / let me think," and Bir düşüneyim is the natural "Let me think it over."
Acele etme, biraz düşüneyim, sonra cevap veririm.
Don't rush, let me think a bit, then I'll answer.
Key forms
All regular; the only thing to watch is the rounded vowel harmony driven by the ü:
| Form | Turkish | Meaning |
|---|---|---|
| Infinitive | düşünmek | to think |
| Present continuous (1sg) | düşünüyorum | I'm thinking |
| Past (1sg) | düşündüm | I thought |
| Aorist (3sg) | düşünür | he/she thinks |
| Negative aorist (1sg) | düşünmem | I don't think / I wouldn't think (of doing) |
| Optative (1sg) | düşüneyim | let me think |
| Imperative (2sg) | düşün | think! |
| Converb | düşünerek | thinking / thoughtfully |
The aorist düşünür is worth a note: it states a habitual or characteristic kind of thinking — "she thinks (that way) / she gives it thought." For reporting your current opinion you normally use the present continuous düşünüyorum, not the aorist, because an opinion held right now is treated as ongoing rather than habitual.
O her şeyi enine boyuna düşünür, aceleci biri değil.
She thinks everything through thoroughly, she's not a hasty person.
"Think that…": the -DIK complement
This is the construction English speakers most often get wrong, because English uses the conjunction "that": "I think that he is right." Turkish has no such word. You nominalize the embedded clause with -DIK, mark its subject with the genitive, and place the whole nominalized clause in the accusative as the object of düşünmek.
The model sentence is haklı olduğunu düşünüyorum ("I think that he is right"):
Onun haklı olduğunu düşünüyorum, bence yanlış yapmadı.
I think that he is right, in my opinion he didn't do anything wrong.
Here ol-duğu-nu breaks down as ol- ("be") + -duğu (-DIK + 3sg possessive) + -nu (accusative), and the subject o surfaces in the genitive as onun. The structure literally reads "his being-right, I think." For a future or hypothetical content, swap -DIK for the future nominalizer -(y)AcAK:
Yarın yağmur yağacağını düşünüyorum, şemsiyeni al.
I think it'll rain tomorrow, take your umbrella.
Bu kararın doğru olmadığını düşünüyoruz.
We think that this decision isn't right.
Negating the content goes inside the nominalized clause (olmadığını, "that it is not"), exactly as in the example above — not on düşünmek itself. This is a recurring feature of Turkish complement clauses: the negation lives where the negated idea lives.
düşünmek versus sanmak
A subtlety English hides: Turkish distinguishes a considered opinion from a mere supposition that may be wrong. düşünmek is "to think" in the sense of a reasoned view; sanmak is "to think / suppose / assume," often with an undertone that the speaker isn't sure or turned out to be mistaken.
Geleceğini sanmıştım ama gelmedi, yanılmışım.
I'd assumed she would come, but she didn't — I was wrong.
Use düşünmek when you mean "this is my judgement"; reach for sanmak when you mean "I'm under the impression / I suppose." Both take the same -DIK complement, so only the verb changes.
düşünce and düşünerek
düşünmek is a productive root. The deverbal noun düşünce means "thought, idea, opinion" (and, in the plural with a darker tint, "worry, concern, things on one's mind"). The converb düşünerek (verb stem + -(y)ArAk) means "by thinking / thoughtfully / while thinking" and describes the manner in which a main action is done.
Aklıma güzel bir düşünce geldi, dinler misin?
A nice idea came to me, will you listen?
Her adımını uzun uzun düşünerek attı.
He took every step thoughtfully, after long consideration.
Common mistakes
❌ Sen düşünüyorum.
Definite object left without the accusative.
✅ Seni düşünüyorum.
I'm thinking about you.
"Think about" puts the object in the accusative — seni, with no separate word for "about."
❌ Düşünüyorum ki haklı.
An English-style 'that' clause instead of the -DIK nominalization.
✅ Haklı olduğunu düşünüyorum.
I think that he is right.
Turkish has no "that"-conjunction here; nominalize with -DIK, genitive subject, accusative clause.
❌ Haklı olduğunu düşünmüyorum.
Negation put on düşünmek when the embedded idea was meant to be negated.
✅ Haklı olmadığını düşünüyorum.
I think that he is not right.
To say "I think he's not right," negate inside the clause: olmadığını. Negating düşünmek itself (düşünmüyorum) changes the meaning to "I don't think (about it)."
❌ Geleceğini düşünmüştüm ama gelmedi.
düşünmek used for a mistaken supposition that calls for sanmak.
✅ Geleceğini sanmıştım ama gelmedi.
I'd assumed she'd come, but she didn't.
For a guess that turned out wrong, sanmak ("suppose, assume") fits better than the reasoned düşünmek.
Key takeaways
- "Think about" = accusative object, no word for "about": seni düşünüyorum.
- "Think that…" = -DIK nominalization
- genitive subject + accusative clause: haklı olduğunu düşünüyorum; use -(y)AcAK for future content.
- Negate the embedded idea (olmadığını), not düşünmek, to say "I think it is not…".
- The aorist düşünür is habitual; use düşünüyorum for a current opinion.
- Prefer sanmak for a supposition that may be (or proved) wrong.
- Derived forms: düşünce ("thought/idea"), düşünerek ("thoughtfully").
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Start learning Turkish→Related Topics
- Nominalized 'That'-ClausesB1 — How Turkish renders English 'that'-complements with -DIK (factual) or -(y)AcAK (future) plus a possessive and case, with the embedded subject in the genitive.
- The Converb -(y)ArAk ('by / while doing')B1 — How -(y)ArAk marks the manner or means of a same-subject action — answering 'how?' rather than sequencing events like -(y)Ip.
- Deverbal Nouns: -GI, -Im, -GIç, -mAnB2 — A family of semi-productive suffixes that turn verbs into nouns — sev- 'love' becomes sevgi 'love', öğret- 'teach' becomes öğretmen 'teacher' — so that once you spot the suffix you can see the verb hiding inside everyday vocabulary.
- sanmak and zannetmek (to suppose/think mistakenly)B1 — How sanmak and its compound twin zannetmek express tentative or mistaken belief, take a -DIK/-AcAk nominalized complement, and differ from neutral düşünmek.