～時・とき (when)

• Reading: とき
• Romaji: toki
• Formation: Verb (plain form) + とき / い-Adj + とき / な-Adj + な + とき / Noun + の + とき
• Kanji breakdown: 時 — time, hour, occasion

Meaning

A dependent noun that indicates the time when someone does, did, or will do something. It connects a modifying clause to a main clause to express temporal context.

とき functions as a temporal noun modified by a preceding clause. When the modifying clause uses past tense (食べたとき), it implies the action was completed before the main clause event. When it uses present tense (食べるとき), the action has not yet been completed at that point. This tense distinction in the modifying clause is independent of the overall sentence tense. とき can also follow nouns directly with の (子供のとき) or na-adjectives with な (暇なとき). It is often written in hiragana in casual contexts and with kanji 時 in formal writing.

Examples

1. 日本に行った時、富士山を見た。 When I went to Japan, I saw Mt. Fuji.
2. 暇なとき、よく映画を見ます。 When I'm free, I often watch movies.
3. 子供のとき、毎日公園で遊んでいた。 When I was a child, I played in the park every day.

Usage Guide

Context: spoken, written, everyday

Tone: descriptive

Do Say

• 困った時は、いつでも連絡してください。
• 寒い時にはコートを着たほうがいい。
• 大学生の時、アルバイトをしていました。
• 寝る時、いつも音楽を聴きます。

Don't Say

• 日本に行く時に、富士山を見た。(Past event in the main clause needs 行った時 to show the trip was completed) → 日本に行った時に、富士山を見た。
• 暇の時、映画を見ます。(な-adjective requires な before とき, not の) → 暇なとき、映画を見ます。
• 子供とき、よく泳いだ。(Noun before とき needs the particle の) → 子供のとき、よく泳いだ。

Origin & History

Derived from the noun 時 (toki, meaning 'time'), which has been used since Old Japanese as both an independent noun and a dependent temporal marker in subordinate clauses.

Cultural Context

Generation: All ages

Social background: Universal