と思う — I Think That

Meaning & Usage

と思う (to omou) means 'I think that...' in English. Use it to express opinions, make guesses, or state intentions. Once you start using it, you'll find it coming up in nearly every conversation.

The particle と (to) functions as a quotation particle — similar to the word 'that' in 'I think that it will rain.' The verb 思う (omou) means 'to think' or 'to feel.' Together, they let you attach your personal view to almost any statement.

と思う expresses the speaker's own thoughts at the moment of speaking. To say what someone else thinks, use と思っている (to omotteiru) — it describes an ongoing mental state rather than an instant reaction. This distinction comes up in Common Mistakes below.

The pattern works in both casual and formal settings. In conversation with friends or family, 明日あしたは雨あめだと思う (I think it'll rain tomorrow) sounds natural without formality markers. In business or academic contexts, switch to と思います (to omoimasu) — same meaning, more appropriate register.

と思う also works as a softener. Rather than declaring something as fact, speakers add it to signal 'this is my view.' Saying おいしいと思う instead of おいしい leaves room for disagreement without awkwardness. This kind of linguistic humility is deeply valued in Japanese culture — it's not uncertainty, it's consideration for others.

と思っています (to omotteimasu) shifts the nuance from opinion to ongoing intention. 日本にほんに行いきたいと思っています means 'I'm thinking of going to Japan' — a plan you currently hold, not a passing thought. Use this form when discussing future goals.

Structure & Formation

The core structure of と思う is straightforward: take any clause in the plain (dictionary) form, add と, and then add 思う (or its polite or past-tense forms).

Basic Pattern: [Clause in plain form] + と + 思う

The clause before と must always be in the plain form — never the polite ます or です form. Here is how it connects to different word types:

For nouns and な-adjectives, you must add だ (the plain form of です) before と. For い-adjectives and verbs, attach と directly. Key polite and tense variations:

• と思う (to omou) — Casual present
• と思います (to omoimasu) — Polite present
• と思わない (to omowanai) — Casual negative
• と思いません (to omoimasen) — Polite negative
• と思った (to omotta) — Casual past: 'I thought that...'
• と思いました (to omoimashita) — Polite past
• と思っている (to omotteiru) — Ongoing state / someone else's thought
• と思っています (to omotteimasu) — Polite ongoing state / intention

Example Sentences

Basic Opinions

Opinions About People

Predictions and Guesses

Expressing Intentions (と思っています)

Past Thoughts

Common Mistakes

Mistake 1: Using the Polite Form Before と思う

❌ 明日あしたは雨あめが降ふりますと思います。

✅ 明日あしたは雨あめが降ふると思います。

The clause before と must always be in the plain (dictionary) form, never the polite ます or です form. A common assumption for beginners: if と思います is polite, the preceding clause should be too. It isn't. Politeness is controlled only by the final verb — the embedded clause always stays in plain form.

Mistake 2: Forgetting だ with Nouns and な-Adjectives

❌ 彼かれは学生がくせいと思います。

✅ 彼かれは学生がくせいだと思います。

When a clause ends with a noun or な-adjective, add だ before と. Without it, the sentence sounds incomplete. Think of the embedded clause as needing its own predicate — だ provides that for nouns and な-adjectives. い-adjectives don't need it because they already function as predicates on their own.

Mistake 3: Using と思う for Another Person's Thoughts

❌ 彼かれはおいしいと思う。 (intended meaning: He thinks it's delicious)

✅ 彼かれはおいしいと思っている。

Simple present と思う is reserved for the speaker's own thoughts. For what someone else is thinking, use と思っている (to omotteiru) — it describes their ongoing mental state. Using と思う with a third-person subject sounds unnatural because the simple form implies direct, first-person access to your own mind.

Mistake 4: Putting と思う in the Wrong Position

❌ と思う日本語にほんごは難むずかしい。

✅ 日本語にほんごは難むずかしいと思う。

と思う always goes at the end of the sentence. The thought comes first; と思う is appended at the close. Unlike English, where 'I think' can open a sentence, Japanese quotation structures always follow the quoted clause. No exceptions.

Mistake 5: Negating 思う Instead of the Inner Clause

❌ 彼女かのじょは来くると思わない。 (sounds unnatural)

✅ 彼女かのじょは来こないと思う。

Japanese speakers prefer to negate the inner clause, not 思う itself. 思わない (I don't think) is grammatically possible, but native speakers almost always say 'I think she won't come' rather than 'I don't think she'll come.' Move the negation inside the quoted clause — this is how people actually talk.

Cultural Notes

Japanese communication puts a premium on keeping harmony. Adding と思う to a statement signals 'this is my perspective' rather than 'this is fact,' making it easy for others to disagree without awkwardness. It's a small phrase that does significant social work — which is why native speakers use it constantly, not just when they're uncertain.

In business settings, と思います signals professionalism and humility. When presenting ideas in a meeting, Japanese professionals almost always close their statements with と思います rather than bold, definitive claims. It leaves room for discussion and shows respect for differing views — core values in Japanese workplace culture.

In everyday situations, と思う signals 'I'm not 100% sure.' Not certain what time a shop closes? Add と思う. Can't quite place someone's name? と思う covers it. It works exactly like 'I think it's around the corner' in English — honest, natural, and low-pressure.

In casual speech with close friends, the と is sometimes dropped — the clause runs into 思う with just a slight pause. For now, stick with the full と思う until you're comfortable with casual registers.

Related Grammar Points

• つもり — Intend To, Plan To (Grammar N5)
• てもいい — May, It's Ok To (Grammar N5)
• たり〜たり — Do Things Like A And B (Grammar N5)
• ないでください — Please Don't (Grammar N5)
• ほうがいい — Should, Had Better (Grammar N5)
• もらう — To Receive (Grammar N5)

JLPT Tips

と思う is a core JLPT N5 grammar point. It appears in listening sections, reading passages, and grammar fill-in questions — getting it right consistently is one of the easiest wins at this level.

First, always remember that the clause before と must be in plain form. Wrong answer choices in multiple-choice questions often include the polite ます or です form before と — don't fall for it. If you see ～ますと思います or ～ですと思います, those are always wrong.

Second, pay special attention to nouns and な-adjectives, which require だ before と. A common test question presents a noun and asks which form correctly attaches to と思う. The right answer always has だ between the noun and と. Missing だ is one of the most frequently tested mistakes at this level.

Third, know the difference between と思う and と思っています. JLPT listening often features dialogues where a character expresses a future intention using と思っています. Recognizing that this form signals an ongoing plan — not a passing opinion — will help you answer comprehension questions accurately.

Fourth, remember the natural negation pattern: negate the inner clause, not 思う. When a test question involves negation with と思う, the expected answer places the negative form inside the quoted clause. This appears in both reading and listening questions.

Finally, drill と思います in polite contexts. It appears constantly in N5 listening and reading — in questions, suggestions, and polite opinions. The more natural it sounds to your ear, the fewer questions you'll miss.