Compound Sentence

Time Clauses: …とき, …てから, …後で, …前に, …あいだに, and …うちに

When: とき

Last time, you learned how to express simultaneous actions, e.g. “テレビをながらべんきょうをしました (I studied while watching TV).” The variety of your expression is greatly increasing now. Then, if you would like to say, “when I was a child, I studied while watching TV,” what should you do? In this lesson, you will learn how to utilize time clauses.

Explanation for How Time Clauses Work in Japanese

Table of Contents
とき and ときに: When
あとで and …てから: After
まえに: Befor
あいだに: One-Time Actions within a Specific Period

Time clauses are types of subordinate clauses, e.g. “when I got up” and “before I went to bed.” You can express more various things by using time clauses because you can set anything as a subject, whereas simultaneous actions require the same subject in main actions and sub actions. Let’s learn how it works.

とき and ときに: When

わたしこまっていたとき あにがいつもたすけてくれ(た / ました)
Time Clause Main Clause
When I was in trouble, my elder brother always helped [me].

とき is grammatically a noun ”時: time” and written in Hiragana or Kanji. By using relative clauses with とき, you can express time clauses like “when” in English. Thus, you can directly connect sentences to とき without using conjugations. When you connect nouns and na-adjectives, you can also use の instead of the state-of-being style, e.g. 学生のとき VS. 学生だったとき. There is a certain difference in nuance between とき and ときに. When you use とき, main clauses should indicate habitual actions, ongoing states, and constant states.

学生がくせいときまつりがき(だった / でした)。
When [I] was a student, [I] liked festivals.
どもだったとき、よくポケモンをして(いた / いました)。
When [I] was a child, [I] often played Pokemon.

When it comes to ときに, the に comes from the particle に which indicates specific time. Therefore, when you use ときに, main clauses should indicate non-habitual actions or one-time events.

学生がくせいときに転車てんしゃ旅行りょこう(した / しました)。
When [I] was a student, [I] traveled by bicycle.
しんときにいて(しまった / しまいました)。
[I] (unintentionally) cried when the earthquake came.

Since it is a relative clause with a noun, you can substitute other words which have similar meanings to とき. For example, you can use “ころ: (approximate) time” which indicates a wider range of time than とき.

学生がくせいころまつりがき(だった / でした)。
学生がくせいころ転車てんしゃ旅行りょこう(した / しました)。

Considering both of the characteristics, if time clauses indicate actions which take place within a short time, とき is more suitable than 頃 and vice versa. Take a look at the following comparison.

しんきたときは使つかってはいけ(ない / ません)。
=> Natural (As for when earthquakes happen, you must not use fire.)
地震が起きた頃は、火を使ってはいけ(ない / ません)
=> Wrong
学生がくせいときまつりがき(だった / でした)。
=> Natural
学生がくせいころまつりがき(だった / でした)。
=> More natural

あとで and …てから: After

メールをおくったあと ちがいをつけ(た / ました)
Time Clause Main Clause
[I] found a mistake after [I] sent the email.

後で and てから are the counterpart to “after” in English. Regarding the conjugation, you attach the ta-form to 後で and the te-form to から. Only 後で allows you to connect nouns by placing の, i.e. “あいあとで: after the game.”

ひらがなをべんきょうしたあとかんべんきょう(する / します)。
After [I] have studied Hiragana, [I] will study Kanji.
なかさんがてからすずさんが(た / ました)。
After Tanaka-san came, Suzuki-san came.
ひるはんあとコーヒーを(んだ / みました)。
After lunch, [I] had a cup of coffee.

The difference between 後で and てから is this: 後で just expresses a sequence of actions while てから puts priority on the first action. With the following examples, てから is more suitable than 後で because the first actions are indispensable for the second actions.

しょってからべんきょうはじめ(よう / ましょう)。
Let’s begin studying after [we] have bought a dictionary.
Come to school after [you] have recovered from the cold.

If main clauses indicate ongoing actions or states, or constant states, you have to drop the で from 後で. In the following comparison, 後 is more suitable because the second action is a progressive tense.

昼ご飯の後で、しばらく寝て(いた / いました)
=> Unnatural
ひるはんあと、しばらくて(いた / いました)。
After lunch, I was sleeping for a while.

Japanese grammar guidebooks usually teach learners 後で, however, native speakers also use 後に in everyday life. The difference is still under discussion among linguists. It is said that when you use 後に, the relation or time between the first action and second action is closer than when using 後で. With the below examples, 後に is more natural because it is a kind of set action for Japanese culture to sequentially greet and bow.

=> Natural, but a little less than below
Japanese people bow soon after greeting.

You can use 後で (Not 後に) as a adverb like “later” and “afterward.” This is not involved with time clauses, but you should know the usage.

あと洗濯せんたく(する / します)よ。
[I] will do washing later.
あと一緒いっしょにごはんべ(ない / ませんか)?
Won’t [you] eat a meal with me later?

まえに: Before

メールをおくまえ ちがいをつけ(た / ました)
Time Clause Main Clause
[I] found a mistake before [I] sent the email.

前に is the counterpart to “before” in English. Regarding the conjugation, you attach the plain form to 前に (Be careful; verbs with 後で has to be in the ta-form). 前に allows you to connect nouns by placing の, i.e. “試合の前に: before the game.”

あそまえ宿しゅくだいを(する / します)。
Before [I] hang out, [I] will do my homework.
先生せんせいまえ弁当べんとうべ(た / ました)。
Before the teacher came, [I] ate lunch.
あいまえれんしゅうを(しよう / しましょう)。
Let’s practice before the game.

If the second action indicates ongoing actions or states, or constant states, you have to drop the に of 前に.

あいまえれんしゅうをして(いた / いました)。
[I] was practicing before the game.
[I] was afraid of Tanaka-san before [I] met him.

You can use 前に as an adverb likewise to 後で. This is not involved with time clauses, but you should know the usage.

まえほんったことが(ある / あります)。
[I] have been to Japan before.
まえすずさんに(った / いました)。
[I] met Suzuki-san before.

あいだに: One-Time Actions within a Specific Period

おやでんをしているあいだに 風呂ふろに(はいった / はいりました)
Time Clause Main Clause
While [my] parent was on the phone, [I] took a bath.

あいだに indicates one-time actions within a specific period like “while” and “within.” Regarding the conjugation, you directly connect verbs which can last for a while like progressive tense and constant states. When you use nouns and na-adjectives, you can also use の instead of だった, i.e. 夜のあいだに VS. 夜だったあいだに. Note: あいだ is sometimes written in Kanji like this 間.

 先生せんせいがいないあいだひるを(する / します)。
[I] will take a nap while the teacher is not there.
 どもているあいだはんを(つくった / つくりました)。
While [my] child was sleeping, [I] made a meal.
よるあいだにあめが(った / りました)。
It rained in the night.

If main clauses express ongoing actions or states, or constant states, you have to drop the に from あいだに.

先生せんせいがいないあいだしゅうして(いた / いました)。
[I] was teaching myself while the teacher was not there.
どもているあいだ、ごはんつくって(いた / いました)。
While [my] kid was sleeping, [I] was making a meal.
よるあいだあめって(いた / いました)。
It was raining during the night.

There is a similar sentence pattern: …うちに. This can express almost the same thing as あいだに. However, you need to pay attention to relations between time clauses and main clauses. Only when time clauses are necessity conditions for main clauses, you can use うちに.

どもているうちにはんを(つくった / つくりました)。
=> Natural
夜のうちに雨が(降った / 降りました)
=> Unnatural

The background behind the first example above is something like the mother has to look after the kid when he/she is awake. Thus, the time when the kid was sleeping is the necessity condition for making a meal. Note: うちに doesn’t have the usage to drop に.


Habitual Actions, Ongoing Actions, Ongoing States, and Constant States One-Time Actions
とき ときに
後で / 後に

If you look at the above chart, you can easily figure out the differences. The particles are the key. The words without the particles requires you to use the one that indicates habitual actions, ongoing actions, ongoing states, or constant states. However, Japanese people may not strictly follow this grammatical rule. Please consider the rules as a basic knowledge to make natural sentences. Next, you will learn how to express reasons and purposes.

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