N3 · Structured courses

Ni Chigai Nai: Must Be

Strong conviction based on evidence. This lesson combines form, context, examples, common mistakes, and practice so you can use the pattern in real communication.

12 minNihongo Hub Editorial TeamPublished 2026-06-06Updated 2026-06-06

Learning objectives

  • Lesson goals: Strong conviction based on evidence.
  • Form and connection: [Plain form] に違ちがいない
  • Nuance in real use: Japanese's closest equivalent to "must be."

Form and connection

[Plain form] に違ちがいない

Core Explanation

Strong conviction based on evidence.

Cultural Note

Japanese's closest equivalent to "must be."

Practical examples

He will surely be late again today.
That building must be the library.
This must be genuine.

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

1. Write the connection formula for this lesson.
Show answer[Plain form] に違ちがいない
2. Explain the meaning of the first example.
Show answerHe will surely be late again today.
3. Rewrite the final example using this lesson pattern.
Show answerこれは本物ほんものに違ちがいない。 ([Plain form] に違ちがいない)

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