Meaning
に違いない expresses the speaker's confident inference or assumption that something is definitely true based on factual reasoning. It conveys certainty about a conclusion drawn from observable evidence. The more polite form is に違いありません. This pattern can follow verbs, i-adjectives, na-adjectives, and nouns in their plain forms.
Formation
| Part of speech | Formation |
|---|---|
| 动词普通形 | に違いない |
| い形容词 | に違いない |
| な形容词 | に違いない |
| 名词 | に違いない |
Examples
-
空気の汚染をこのままにしておくと、人々の健康に悪い影響を与えるに違いありません。
If we leave air pollution as it is, it will definitely have negative effects on people's health. -
真夏だし、明日も晴れて暑いに違いない。
Since it's midsummer, tomorrow must be sunny and hot as well. -
不動産屋の人に、この辺りは夜は静かに違いないといわれましたが、実際はのら猫が多くて、とてもうるさい。
The real estate agent told me that this neighborhood is certainly quiet at night, but in reality there are many stray cats and it's very noisy. -
スーパーの前に立っている黒いコートの女の人は、わたしの母に違いありません。
That woman in a black coat standing in front of the supermarket must definitely be my mother.
Summary
- Used to express confident deduction or strong certainty based on factual reasoning
- Attaches to plain forms of verbs, i-adjectives, na-adjectives, and nouns
- More formal/polite version is に違いありません; commonly used in both spoken and written Japanese