Learning objectives
- Lesson goals: Learn ni souinai for strong conviction — "must be." Formal, written.
- Form and connection: [Noun/Plain form] に相違そういない
- Nuance in real use: に相違ない is one of the strongest assertions in written Japanese — it declares a conclusion on paper that brooks no argument. In legal documents and news reports, this expression carries unchallengeable authority.
Form and connection
Core Explanation
Learn ni souinai for strong conviction — "must be." Formal, written.
Cultural Note
Practical examples
Common pitfalls
Build the base form before adding the pattern
Complete the required conjugation first. Do not keep polite and plain endings at the same time.
Match politeness to the situation
The examples are reliable starting points; relationships and context can still change the most natural wording.
Practice and answers
Show answer
[Noun/Plain form] に相違そういないShow answer
He must be the culprit.Show answer
この書類しょるいは本物ほんものに相違そういない。 ([Noun/Plain form] に相違そういない)Continue learning
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