In Japanese, expressing certainty or strong assumptions is essential for clear communication. One useful expression for this is 〜に違ちがいない. This grammar structure conveys a high level of confidence about something, often based on reasoning or evidence.

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What Does 〜に違ちがいない Mean?

〜に違ちがいない translates to “must be,” “surely,” or “there’s no doubt that” in English. It’s used when you are almost certain about something, even without direct confirmation. This expression is often employed in both written and spoken Japanese to convey strong convictions or logical conclusions.

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How to Use 〜に違ちがいない

The structure of 〜に違ちがいない is as follows:

✅【Noun】【Na-adjective】【I-adjective】 + に違ちがいない

✅【Verb (plain form)】 + に違ちがいない

Examples:

• Noun
  彼かれは犯人はんにんに違ちがいない。
  He must be the culprit.

• Na-adjective
  彼女かのじょは元気げんきに違ちがいない。
  She must be fine.

• I-adjective
  この問題もんだいは難むずかしいに違ちがいない。
  This problem must be difficult.

• Verb
  彼かれはもう家いえに帰かえったに違ちがいない。
  He must have already gone home.

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More Example Sentences

Nouns

• この料理りょうりを作つくった人ひとはプロに違ちがいない。
  The person who made this dish must be a professional.
• 彼かれは毎朝まいあさジョギングをしている。健康けんこうに違ちがいない。
  He goes jogging every morning. He must be healthy.

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I-Adjectives

• このケーキは甘あまいに違ちがいない。
  This cake must be sweet.
• この映画えいがは面白おもしろいに違ちがいない。予告編よこくへんを見みただけでワクワクする。
  This movie must be interesting. Just watching the trailer makes me excited.

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Na-Adjectives

• この部屋へやは静しずかだ。集中しゅうちゅうできるに違ちがいない。
  This room is quiet. I’m sure I can concentrate.
• レビューで評判ひょうばんがいいから、このホテルは快適かいてきに違ちがいない。。
  As it has good reviews, this hotel must be comfortable.

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Verbs (plain forms)

• 電車でんしゃが遅おくれている。駅えきでたくさんの人ひとが待まっているに違ちがいない。
  The train is delayed. Surely many people are waiting at the station.
• 空そらが暗くらくなってきた。雨あめが降ふるに違ちがいない。
  The sky is getting dark. It’s surely going to rain.

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Summary

• 〜に違ちがいない expresses strong certainty or a confident assumption.
• It can follow verbs, i-adjectives, na-adjectives, and nouns.
• Often used when making logical conclusions based on observation or context.
• Stronger than 〜そうだ or 〜らしい, which are based on appearances or hearsay.

By incorporating 〜に違ちがいない into your Japanese, you can express your thoughts with greater confidence and nuance.

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