「～とき」- Temporal Clause

Explanation

～とき is an important grammatical structure in Japanese that means "when" or "at the time of." It is used to describe the stage or point in time when an action occurs. Pronounced as 「とき」, it can connect with verbs, adjectives, and nouns to indicate events happening at a specific time or stage.

Grammar Patterns

Grammar Point	Connection	Explanation
Verb Dictionary Form + とき	Verb Dictionary Form + とき	Indicates a point in time before the action is completed.
Verb Past Form + とき	Verb Past Form + とき	Indicates a point in time after the action is completed.
い-Adjective + とき	い-Adjective + とき	Indicates a point in time during a certain state.
な-Adjective + な + とき	な-Adjective + な + とき	Indicates a point in time during a certain state.
Noun + の + とき	Noun + の + とき	Indicates a specific point in time.

Basic Examples

• これからこれから食べ物たべものを買かいに行いくときだが、一緒いっしょに食べ物たべものを買かってくれますか。
• Kore kara tabemono o kai ni iku toki da ga, issho ni tabemono o katte kuremasu ka.
• When I go to buy food later, can you buy it with me?
  

Detailed Explanation

1. Verb Dictionary Form + とき

When using the verb dictionary form with とき, it indicates a point in time before the action is completed. For example:

• 日本にほんへ来くるとき、空港くうこうで写真しゃしんを撮とります。
• Nihon e kuru toki, kuukou de shashin o torimasu.
• When I come to Japan, I take photos at the airport.
  

2. Verb Past Form + とき

When using the verb past form with とき, it indicates a point in time after the action is completed. For example:

• 日本にほんへ来きたとき、空港くうこうで写真しゃしんを撮とりました。
• Nihon e kita toki, kuukou de shashin o torimashita.
• When I came to Japan, I took photos at the airport.
  

3. い-Adjective + とき

When using an い-adjective with とき, it indicates a point in time during a certain state. For example:

• 母ははは若わかいとき看護士かんごしでした。
• Haha wa wakai toki kangoshi deshita.
• When my mother was young, she was a nurse.
  

4. な-Adjective + な + とき

When using a な-adjective with とき, you need to add 「な」. For example:

• 桜さくらの花はながきれいなとき、リーさんリーさんは日本にほんへ来きました。
• Sakura no hana ga kirei na toki, Riisan wa Nihon e kimashita.
• When the cherry blossoms were beautiful, Mr./Ms. Lee came to Japan.
  

5. Noun + の + とき

When using a noun with とき, you need to add 「の」. For example:

• 高校生こうこうせいのとき、日本にほんへ留学りゅうがくしたことがあります。
• Koukousei no toki, Nihon e ryuugaku shita koto ga arimasu.
• When I was in high school, I studied abroad in Japan.
  

Deep Dive

Temporal Relationship Between Actions

When both S1 and S2 predicates are verbs, ～とき can be used to indicate the temporal relationship between the actions.

Form	Meaning	Example
V1 (Non-Past) + とき、V2	V2 occurs before V1 is completed	日本にほんへ来くるとき、空港くうこうで写真しゃしんを撮とります。 (Before coming to Japan, I take photos at the airport)
V1 (Past) + とき、V2	V2 occurs after V1 is completed	日本にほんへ来きたとき、空港くうこうで写真しゃしんを撮とりました。 (After coming to Japan, I took photos at the airport)

Usage with Stative Verbs

When the verb in S1 is a stative verb (e.g., 「いる」「ある」) and the predicate in S2 is in the past tense, the verb in S1 can be either in the non-past or past form. For example:

• 部屋へやにいるとき、電話でんわしました。
• Heya ni iru toki, denwa shimashita.
• When I was in the room, I made a phone call.
  

• 部屋へやにいたとき、電話でんわしました。
• Heya ni ita toki, denwa shimashita.
• When I was in the room, I made a phone call.
  

Comparison and Differences

Difference Between ～とき and ～たとき

～とき and ～たとき have subtle differences in usage. ～とき indicates a point in time before the action is completed, while ～たとき indicates a point in time after the action is completed. For example:

• 日本にほんへ来くるとき、空港くうこうで写真しゃしんを撮とります。
• Nihon e kuru toki, kuukou de shashin o torimasu.
• Before coming to Japan, I take photos at the airport.
  

• 日本にほんへ来きたとき、空港くうこうで写真しゃしんを撮とりました。
• Nihon e kita toki, kuukou de shashin o torimashita.
• After coming to Japan, I took photos at the airport.
  

Real-Life Scenarios

Usage in Daily Conversations

• 学校がっこうに行いくとき、必かならず宿題しゅくだいを持もっていってください。
• Gakkou ni iku toki, kanarazu shukudai o motte itte kudasai.
• When you go to school, please always bring your homework.
  

• 映画えいがを見みるとき、静しずかにしてください。
• Eiga o miru toki, shizuka ni shite kudasai.
• When watching a movie, please be quiet.
  

Usage in Specific Scenarios

• 旅行りょこうに行いくとき、パスポートパスポートを持もっていくのを忘わすれないでください。
• Ryokou ni iku toki, pasupooto o motte iku no o wasurenaide kudasai.
• When you go on a trip, don’t forget to bring your passport.
  

Summary

～とき is used in Japanese to indicate a specific point in time or stage when something happens. Mastering its basic usage and application scenarios can help improve your Japanese language skills.