Chapter 25 — Before, After, When, While

You can now describe actions, explain reasons, make requests, give and receive things, and navigate polite and plain speech. What you cannot yet do is connect events in time. You cannot say "before eating," "after working," "when I was a child," or "while listening to music." These four time constructions — 前に, 後で, 時, and ながら — are among the most frequently used connectors in Japanese. They appear in nearly every narrative, every explanation of daily routine, every account of past events.

This chapter teaches all four. Three of them are straightforward. One of them — 時 — is genuinely difficult, because the tense of the verb before 時 changes the meaning in a way that has no parallel in English. That section will receive the most attention.

25.1 前に — "Before"

Formation

前に means "before." It attaches to two types of expressions.

With verbs: Use the dictionary form (the plain non-past affirmative form) directly before 前に.

たべる 前に てを あらいます。 "I wash my hands before eating."

ねる 前に ほんを よみます。 "I read a book before going to sleep."

でかける 前に てんきよほうを みます。 "I check the weather forecast before going out."

With nouns: Insert の between the noun and 前に.

しごとの 前に コーヒーを のみます。 "I drink coffee before work."

しけんの 前に たくさん べんきょうしました。 "I studied a lot before the exam."

ごはんの 前に てを あらってください。 "Please wash your hands before the meal."

The verb before 前に is always dictionary form

This is the most important rule for 前に. The verb that comes before 前に is always in the dictionary form — the plain non-past affirmative. This is true regardless of when the event happened, regardless of whether the main clause is past or non-past, affirmative or negative.

Look at these examples:

にほんに いく 前に にほんごを べんきょうしました。 "I studied Japanese before going to Japan."

The main clause is past tense (べんきょうしました). But the verb before 前に is still いく, not いった. The reason is logical: 前に marks an action that has not yet happened at the time of the main clause. "Before going" means the going has not occurred yet. Since the action is unrealized at the relevant moment, it stays in the non-past form.

More examples:

がっこうに くる 前に あさごはんを たべましたか。 "Did you eat breakfast before coming to school?"

でんしゃに のる 前に きっぷを かってください。 "Please buy a ticket before getting on the train."

くにに かえる 前に ともだちに おみやげを あげました。 "I gave my friends souvenirs before returning to my country."

In every case, the verb before 前に is in the dictionary form. Do not change this to the past tense. Even if you are talking about something that happened years ago, the verb before 前に stays non-past. This rule has no exceptions.

Common mistake

✗ たべた 前に てを あらいました。 ✓ たべる 前に てを あらいました。

If you put the た-form before 前に, it is ungrammatical. This is a mistake that learners make frequently because English says "before I ate" with a past-tense verb. Japanese does not work this way. The action before 前に is always expressed in the dictionary form because it has not yet happened at the moment being described.

前に as a standalone time expression

前に by itself, without a verb or noun before it, means "before" in the sense of "previously" or "some time ago."

前に にほんに いったことが あります。 "I have been to Japan before."

その えいがは 前に みました。 "I saw that movie before (previously)."

This standalone use is different from the grammatical pattern covered in this section, but it is worth noting because you will encounter it frequently.

25.2 後で — "After"

Formation

後で means "after." Like 前に, it attaches to verbs and nouns.

With verbs: Use the た-form (plain past affirmative) before 後で.

たべた 後で さんぽします。 "I take a walk after eating."

しごとが おわった 後で ともだちに あいます。 "I meet my friend after work ends."

シャワーを あびた 後で ねます。 "I go to bed after taking a shower."

With nouns: Insert の between the noun and 後で.

しごとの 後で いっぱい のみましょう。 "Let's have a drink after work."

じゅぎょうの 後で せんせいに しつもんしました。 "I asked the teacher a question after class."

しけんの 後で カラオケに いきませんか。 "Would you like to go to karaoke after the exam?"

The verb before 後で is always た-form

This is the counterpart to the 前に rule. The verb before 後で is always in the た-form — the plain past affirmative. This is true regardless of when the main clause occurs.

にほんに いった 後で ちゅうごくにも いきました。 "After going to Japan, I also went to China."

ひるごはんを たべた 後で すこし やすみます。 "I rest a bit after eating lunch."

The logic mirrors 前に. 後で marks an action that has already been completed at the time of the main clause. "After eating" means the eating is finished. Since the action is completed at the relevant moment, it appears in the past form.

後で versus 後に

You will encounter both 後で and 後に. Both are correct, and the meaning is the same.

たべた 後で さんぽします。 たべた 後に さんぽします。

Both mean "I take a walk after eating." In conversation, 後で is more common. In writing, 後に appears more frequently. At this level, use whichever you encounter first — both are natural and correct.

Common mistake

✗ たべる 後で さんぽします。 ✓ たべた 後で さんぽします。

The dictionary form before 後で is ungrammatical. The action must be completed before the main clause can occur, so the past form is required. This is the mirror image of the 前に rule.

前に and 後で as a pair

It helps to think of these two as a matched set:

This pairing is logical and consistent. The tense before the time word reflects the status of the action at the moment being described, not the tense of the overall sentence. Once this logic clicks, both rules become easy to remember.

25.3 時 — "When"

時 means "when" or "at the time of." It is the most versatile of the four time constructions in this chapter — and the most difficult, because the tense of the clause before 時 changes the meaning in a way that beginners find counterintuitive.

Basic formation

時 connects to different predicate types as follows:

Notice the な for な-adjectives and the の for nouns. These are the same patterns you see before ので and んです. When a modifier connects to a noun-like word (and 時 functions as a noun meaning "time"), な-adjectives take な and nouns take の.

Simple uses with adjectives and nouns

With adjectives and nouns, 時 is straightforward. There is no tense complication.

さむい 時 あたたかい ものを のみたいです。 "When it's cold, I want to drink something warm."

ひまな 時 なにを しますか。 "What do you do when you're free?"

わかい 時 よく スポーツを しました。 "When I was young, I often played sports."

がくせいの 時 まいにち じてんしゃで がっこうに いきました。 "When I was a student, I went to school by bicycle every day."

こどもの 時 やさいが きらいでした。 "When I was a child, I didn't like vegetables."

These uses are intuitive and cause little trouble. The difficulty begins with verbs.

The tense distinction with verbs — the core difficulty

With verbs, the form before 時 — dictionary form or た-form — changes the meaning. This is the most important concept in this chapter. Read this section carefully.

Dictionary form + 時 means "when about to do" or "when on the way to doing." The action described by the verb has not yet been completed at the time the main clause occurs.

た-form + 時 means "when having done" or "after doing." The action described by the verb has already been completed at the time the main clause occurs.

This distinction controls the entire meaning of the sentence.

Example 1: いく versus いった

日本に いく 時 くうこうで おみやげを かいました。 "When I was going to Japan, I bought souvenirs at the airport."

Here, いく 時 uses the dictionary form. The going to Japan has not happened yet at the time of buying souvenirs. The speaker bought the souvenirs while still at the departure airport — before arriving in Japan. The souvenirs were purchased on the way there.

日本に いった 時 おみやげを かいました。 "When I went to Japan, I bought souvenirs."

Here, いった 時 uses the た-form. The going to Japan has already happened. The speaker was already in Japan when they bought the souvenirs. They bought them while there, or on the way back — but the point is that the arrival in Japan was complete before the buying occurred.

Same words. Different verb form. Different meaning. This distinction matters.

Example 2: でかける versus でかけた

でかける 時 かぎを わすれました。 "When I was leaving, I forgot my keys."

The leaving has not been completed. The speaker was in the process of heading out — still at home or at the door — and realized they forgot their keys. The forgetting happened before the departure was complete.

でかけた 時 かぎを わすれました。 "When I went out, I forgot my keys."

The leaving has been completed. The speaker had already left and then discovered that they had forgotten their keys. Perhaps they reached the station and realized the keys were at home. The discovery happened after the departure.

Example 3: かえる versus かえった

うちに かえる 時 スーパーに よりました。 "On the way home, I stopped by the supermarket."

かえる 時 — dictionary form. The returning home has not been completed yet. The speaker was on their way home when they stopped at the supermarket. The stop happened during the journey, before arriving home.

うちに かえった 時 ねこが ソファーで ねていました。 "When I got home, the cat was sleeping on the sofa."

かえった 時 — た-form. The returning home has been completed. The speaker was already at home when they saw the cat. The observation happened after arriving.

Example 4: あう versus あった

ともだちに あう 時 いつも カフェに いきます。 "When I meet my friend, we always go to a cafe."

あう 時 — dictionary form. This describes a habitual pattern. Each time, the meeting is about to happen, and the chosen venue is a cafe. The two events are essentially simultaneous — the meeting occurs at the cafe.

ともだちに あった 時 びっくりしました。 "When I met my friend, I was surprised."

あった 時 — た-form. The meeting has occurred. At the moment of encountering the friend (the meeting being complete), the speaker felt surprise. Perhaps the friend looked different, or the meeting was unexpected.

How to choose the correct form

Ask yourself one question: At the moment the main clause happens, has the 時-clause action been completed?

• If no — the action is not yet complete, is in progress, or is about to happen — use the dictionary form.
• If yes — the action is complete, finished, done — use the た-form.

This is not about when the overall sentence takes place. It is about the relationship between the two events within the sentence.

More examples for practice

としょかんで べんきょうする 時 いつも コーヒーを もっていきます。 "When I study at the library, I always bring coffee."

Dictionary form. The studying has not started yet at the moment of bringing coffee. The speaker brings coffee on the way to study — before the studying begins.

としょかんで べんきょうした 時 となりの ひとが うるさかったです。 "When I studied at the library, the person next to me was noisy."

た-form. The speaker was in the process of studying (the studying was underway, the situation of "having gone to study" was complete) when the noise occurred. The studying context was established before the noise was noticed.

この くすりは あたまが いたい 時 のんでください。 "Please take this medicine when you have a headache."

い-adjective before 時. Straightforward — "when your head hurts."

ひまな 時 でんわしてください。 "Please call me when you're free."

な-adjective before 時. The な before 時 is required.

はじめて にほんに いった 時 なにも わかりませんでした。 "When I first went to Japan, I didn't understand anything."

た-form. The arrival in Japan was complete, and the speaker found themselves not understanding anything upon being there.

にほんに いく 時 パスポートが いります。 "When you go to Japan, you need a passport."

Dictionary form. You need the passport before you have arrived — it is required for the process of going. The going has not been completed at the point when the passport is needed.

Summary table for 時

The mistake to avoid

Do not assume that the tense before 時 must match the tense of the main clause. It does not. The two are independent. You can have a past-tense main clause with a dictionary-form verb before 時, and a non-past main clause with a た-form verb before 時.

にほんに いく 時 くうこうで おみやげを かいました。 (dictionary form before 時 + past main clause — both are correct together)

しゅくだいが おわった 時 いつも テレビを みます。 "When I've finished homework, I always watch TV." (た-form before 時 + non-past main clause — both are correct together)

The tense before 時 describes the relationship between the two events. The tense of the main clause describes when the overall situation occurs. These are two separate questions, and they are answered independently.

25.4 ながら — "While"

Formation

ながら attaches to the ます-stem of a verb. The ます-stem is the form you get when you remove ます from the polite form.

Meaning: two simultaneous actions

ながら connects two actions that happen at the same time, performed by the same person. The ながら clause describes the secondary or background action. The main clause describes the primary action.

おんがくを ききながら べんきょうします。 "I study while listening to music."

The primary action is studying. The secondary action is listening to music. Both happen at the same time. ながら marks the listening as the background activity.

テレビを みながら ごはんを たべます。 "I eat while watching TV."

The primary action is eating. Watching TV is the background.

コーヒーを のみながら しんぶんを よみます。 "I read the newspaper while drinking coffee."

The primary action is reading. Drinking coffee is the background.

Which action is which?

The action attached to ながら is always the secondary (background) action. The main clause is always the primary action. In English, "while" can introduce either the primary or secondary action, which sometimes causes confusion. In Japanese, the rule is fixed:

[secondary action] ながら [primary action]

If you want to say "I listen to music while studying," where studying is the background and music is the primary activity, you would reverse the structure:

べんきょうしながら おんがくを ききます。

Now studying is the ながら clause (background), and listening to music is the main clause (primary). The meaning has shifted: the speaker's main activity is listening to music, and they happen to be studying at the same time. This reversal is possible but sounds unusual — listening to music as a primary activity with studying in the background suggests the speaker is not very serious about the studying.

In practice, think about which action has the speaker's focus. That action goes in the main clause. The other action, the one happening alongside it, goes in the ながら clause.

Same-subject restriction

Both actions in a ながら sentence must be performed by the same person. You cannot use ながら when two different people are performing the two actions.

✓ わたしは おんがくを ききながら そうじします。 "I clean while listening to music." (same person does both)

✗ わたしが りょうりを しながら つまが テレビを みています。 (Two different people — ながら cannot be used this way.)

To express simultaneous actions by different people, use 間 (あいだ) — a pattern you will learn later. For now, remember: ながら requires one person doing two things at once.

More examples

あるきながら でんわで はなさないでください。 "Please don't talk on the phone while walking."

はしりながら おんがくを きくのが すきです。 "I like listening to music while running."

ともだちと はなしながら ひるごはんを たべました。 "I ate lunch while talking with my friend."

わらいながら はなしました。 "They spoke while laughing."

なきながら いえに かえりました。 "I went home crying." (literally: "while crying, I returned home")

The last two examples show that ながら works well with actions that describe manner — laughing, crying, singing. In these cases, the ながら clause tells you how the main action was performed.

25.5 Comparing the Four Patterns

Now that you have seen all four, here is a summary of how they relate to each other.

前に and 後で are a natural pair — one marks what comes before, the other what comes after. The verb-form rule for each is consistent with its meaning.

時 stands alone as the most flexible and most complex. It can mean "when about to do," "when having done," "when in a state of," or "at the time of," depending on what precedes it.

ながら is different from the other three because it does not sequence events. It layers them — two actions happening at the same time.

25.6 Reading Passage

あさの じかん

わたしは まいあさ ろくじに おきます。おきた 後で まず かおを あらいます。それから、コーヒーを いれます。コーヒーを のみながら ニュースを みるのが あさの しゅうかんです。

しごとに いく 前に おべんとうを つくります。きのうは じかんが なかったので、おべんとうを つくらないで いえを でました。しごとの ひるやすみに コンビニで おべんとうを かいました。

かいしゃに ついた 時 もう かいぎが はじまっていました。「すみません、でんしゃが おくれたんです」と いいました。

ひるやすみの 時 どうりょうと いっしょに そとで ごはんを たべました。どうりょうは ラーメンを たべながら しごとの はなしを していました。わたしは 「ひるやすみの 時 ぐらい しごとの ことを わすれましょうよ」と いいました。

しごとが おわった 後で スーパーに よりました。うちに かえる 時 きれいな ゆうやけが みえました。うちに かえった 時 ねこが げんかんで まっていました。

ばんごはんを たべる 前に ねこに ごはんを やりました。ばんごはんの 後で すこし にほんごを べんきょうしました。おんがくを ききながら ほんを よんで、じゅういちじに ねました。

いそがしい 一日でしたが、いい 一日でした。

Translation

Morning Time

I wake up at six every morning. After waking up, I first wash my face. Then I make coffee. Drinking coffee while watching the news is my morning routine.

I make a boxed lunch before going to work. Yesterday I didn't have time, so I left the house without making a lunch box. I bought a boxed lunch at the convenience store during the lunch break at work.

When I arrived at the company, the meeting had already started. "I'm sorry, the train was delayed," I said.

During the lunch break, I ate outside together with a colleague. My colleague was talking about work while eating ramen. I said, "At least during the lunch break, let's forget about work."

After work ended, I stopped by the supermarket. On the way home, I could see a beautiful sunset. When I got home, the cat was waiting at the entrance.

Before eating dinner, I fed the cat. After dinner, I studied Japanese a little. I listened to music while reading a book, and went to bed at eleven.

It was a busy day, but it was a good day.

Passage Notes

This passage uses all four time constructions from this chapter. Here is where each appears:

• おきた 後で — "after waking up." た-form before 後で, as required.
• のみながら — "while drinking." ます-stem before ながら.
• いく 前に — "before going." Dictionary form before 前に.
• ついた 時 — "when I arrived." た-form before 時. The arrival was complete, and upon arriving, the meeting had already started.
• ひるやすみの 時 — "during the lunch break." Noun + の before 時.
• たべながら — "while eating." ます-stem before ながら.
• おわった 後で — "after ending." た-form before 後で.
• かえる 時 — "when going home / on the way home." Dictionary form before 時. The returning was not yet complete — the speaker was still on the way and saw the sunset.
• かえった 時 — "when I got home." た-form before 時. The returning was complete — the speaker was already home and saw the cat.
• たべる 前に — "before eating." Dictionary form before 前に.
• 後で — "after dinner." Noun + の + 後で.
• ききながら — "while listening." ます-stem before ながら.

Pay special attention to the contrast between かえる 時 and かえった 時 in the same paragraph. The first describes something that happened on the way home (returning not yet complete). The second describes something that happened upon arriving home (returning complete). This is exactly the tense distinction discussed in Section 25.3.

Reading Passage 2 — おしょうがつ

にほんの おしょうがつは いちがつの はじめです。おおみそか — つまり じゅうにがつ さんじゅういちにち — の よるから おしょうがつの じゅんびが はじまります。

わたしの かぞくは まいとし おなじことを します。まず、としを こす 前に いえを きれいに そうじします。そうじが おわった 後で みんなで としこしそばを たべます。そばは ほそくて ながい たべものなので、「ながい いのち」の いみが あるそうです。

そばを たべながら テレビの おんがく ばんぐみを みます。よなかの じゅうにじに なる 時 おてらの かねが なります。これは 「じょやのかね」と いいます。かねの おとを ききながら あたらしい としを むかえます。

がんじつ — いちがつ ついたち — の あさ、おきた 後で かぞくに 「あけまして おめでとうございます」と いいます。それから おぞうにを たべます。おぞうには おもちが はいった スープです。

あさごはんの 後で ちかくの じんじゃに いきます。これは 「はつもうで」です。じんじゃに ついた 時 いつも ひとが たくさん ならんでいます。さむい 中で まっている 間 あたたかい あまざけを のむ ひとも います。おまいりを した 後で おみくじを ひきます。きょねんは 「きち」でしたが、ことしは なにが でるかな。

おしょうがつの 間 こどもたちは おとしだまを もらいます。おとしだまは おかねの プレゼントです。こどもたちに とって、おしょうがつで いちばん たのしいのは たぶん おとしだまですね。

Passage Notes

This passage uses all four time patterns plus ～てから in the context of real Japanese New Year traditions.

• としを こす 前に — "before crossing into the new year." Dictionary form before 前に.
• おわった 後で — "after finishing." た-form before 後で.
• たべながら — "while eating." ます-stem before ながら.
• じゅうにじに なる 時 — "when it becomes midnight." Dictionary form before 時 — the moment has not yet arrived.
• ききながら — "while listening." ます-stem before ながら.
• おきた 後で — "after waking up." た-form before 後で.
• ついた 時 — "when we arrived." た-form before 時 — the arrival was complete, and upon arriving, people were already lined up.
• まっている 間 — "while waiting." ている before 間. The waiting is ongoing.
• した 後で — "after doing." た-form before 後で.
• おしょうがつの 間 — "during New Year." Noun + の before 間.

Cultural vocabulary: おおみそか (New Year's Eve), としこしそば (year-crossing soba), じょやのかね (New Year's Eve bell), がんじつ (New Year's Day), おぞうに (mochi soup), はつもうで (first shrine visit), おみくじ (fortune slip), おとしだま (New Year's money gift), あまざけ (sweet sake).

25.7 Chapter Summary

This chapter introduced four time-connecting patterns.

前に — "before"

• Verb (dictionary form) + 前に
• Noun + の + 前に
• The verb before 前に is always dictionary form, regardless of the main clause tense

後で — "after"

• Verb (た-form) + 後で
• Noun + の + 後で
• The verb before 後で is always た-form
• 後に is also acceptable (same meaning, slightly more formal)

時 — "when"

• Verb (dictionary form) + 時 = action not yet completed at the time of the main clause
• Verb (た-form) + 時 = action already completed at the time of the main clause
• い-adjective + 時
• な-adjective + な + 時
• Noun + の + 時
• The tense before 時 does not need to match the tense of the main clause

ながら — "while"

• ます-stem + ながら
• The ながら clause is the secondary (background) action
• Both actions must be performed by the same person

The key takeaway from this chapter is the relationship between verb form and meaning. 前に always takes dictionary form because its action is unrealized. 後で always takes た-form because its action is completed. 時 takes either form, and the choice changes the meaning. ながら takes the ます-stem and describes simultaneity. Each pattern has its own logic, and that logic is consistent.

Vocabulary

New words introduced in this chapter: