～のは～だ (it is ~ that)

• Reading: のは〜だ
• Romaji: no wa ~ da
• Formation: Clause + のは + Focused element + だ

Meaning

A cleft sentence structure that highlights new or important information by placing it between のは and だ. It draws attention to a specific element by restructuring the sentence.

The のは～だ structure is Japanese's version of a cleft sentence, similar to 'It is X that...' in English. By moving the most important piece of information to the end position before だ, the speaker emphasizes it. For example, instead of saying 田中さんが窓を割った (Tanaka broke the window), one can say 窓を割ったのは田中さんだ (the one who broke the window is Tanaka) to emphasize who did it. The element placed before だ receives the information focus. This structure is extremely useful for answering questions, making corrections, or highlighting contrasts. のは can also be replaced by のが when the focused element takes が naturally. The pattern works with verbs, adjectives, and nouns in the predicate position.

Examples

1. この本を書いたのは有名な作家だ。 The one who wrote this book is a famous author.
2. 一番大切なのは健康です。 The most important thing is health.
3. 彼が怒っているのは約束を破ったからだ。 The reason he is angry is that I broke a promise.

Usage Guide

Context: spoken, written, everyday

Tone: emphatic

Do Say

• 電話をかけたのは母です。
• 旅行で一番楽しかったのは温泉だった。
• 試合に負けたのは練習不足のせいだ。

Don't Say

• この本を書いたのは有名な作家が書いた。(The focused element after のは should not repeat the verb from the のは clause — just state the answer: 有名な作家だ) → この本を書いたのは有名な作家だ。
• 一番大切のは健康です。(A な-adjective before の requires な: 大切なの) → 一番大切なのは健康です。

Origin & History

This cleft construction uses the nominalizer の to turn a clause into a noun phrase, は to mark it as the topic, and だ to identify the focused information. It mirrors information-focus structures found across many languages.

Cultural Context

Generation: All ages

Social background: Universal