N4Chapter 28

Conditional (〜たら)

Learning objectives

  • Conjugate verbs, adjectives, and nouns into the 〜たら conditional form.
  • Express hypothetical 'if' statements.
  • Express sequential 'when/after' statements.
  • Understand the nuance of 〜たら compared to English 'if/when'.
N4 context

In English, we have “if” for hypothetical situations and “when” for guaranteed future events. Japanese handles conditionals quite differently. There are four main conditional forms (と, ば, たら, なら), but 〜たら is the most versatile and common in daily conversation. It can mean both “if” and “when/after” depending on the context!

Anime pixel-art illustration of a learner at a signpost where possible paths branch toward rain, travel, work, meals, and snowy discoveries.

1. Forming 〜たら

The rule for making the 〜たら form is extremely simple: Take the plain past tense (TA-form) of any word, and add ら.

Verbs

Take the plain past tense (the た/だ form) and add ら.

  • 飲む (nomu) ➔ 飲んだ (nonda) ➔ 飲んだら (nondara)
  • 食べる (taberu) ➔ 食べた (tabeta) ➔ 食べたら (tabetara)
  • する (suru) ➔ した (shita) ➔ したら (shitara)
  • 来る (kuru) ➔ 来た (kita) ➔ 来たら (kitara)

I-Adjectives

Take the past tense (drop い, add かった) and add ら.

  • 安い (yasui) ➔ 安かった (yasukatta) ➔ 安かったら (yasukattara)
  • いい (ii) ➔ よかった (yokatta) ➔ よかったら (yokattara)

Na-Adjectives and Nouns

Take the past tense (add だった) and add ら.

  • 暇 (hima) ➔ 暇だった (himadatta) ➔ 暇だったら (himadattara)
  • 雨 (ame) ➔ 雨だった (amedatta) ➔ 雨だったら (amedattara)

Negative Forms

Take the negative past tense (〜なかった) and add ら.

  • 飲まない ➔ 飲まなかった ➔ 飲まなかったら
  • 安くない ➔ 安くなかった ➔ 安くなかったら
  • 雨じゃない ➔ 雨じゃなかった ➔ 雨じゃなかったら

2. Hypothetical Condition (“If”)

The most straightforward use of 〜たら is for hypothetical conditions. If Condition A happens, then Action B will happen. It is often paired with the adverb もし (moshi) at the beginning of the sentence to emphasize that it is a hypothetical “if”.

Grammar文法
(もし) A〜たら、B。

means If A happens / If A is true, then B.

Formation

Ta-form + ら

Examples

もし雨が降ったら、行きません。

moshi ame ga futtara, ikimasen.

If it rains, I will not go.

安かったら、買います。

yasukattara, kaimasu.

If it's cheap, I will buy it.

時間がなかったら、手伝ってください。

jikan ga nakattara, tetsudatte kudasai.

If you don't have time, please help me.

[!TIP] もし (moshi) is completely optional! The 〜たら at the end of the clause already carries the “If” meaning. もし just gives the listener an early warning that an “If” statement is coming.

3. Sequential Condition (“When / After”)

This is where 〜たら often confuses English speakers. If the condition (A) is guaranteed to happen in the future, 〜たら no longer means “If”. It means “When” or “After”.

It implies a strong sequence: First A must completely finish, and THEN B will happen.

Grammar文法
A〜たら、B。

means When A happens / After A finishes, then B.

Formation

Ta-form + ら

Examples

日本に着いたら、電話します。

Nihon ni tsuitara, denwa shimasu.

When/After I arrive in Japan, I will call you.

仕事が終わったら、飲みに行きましょう。

shigoto ga owattara, nomi ni ikimashou.

When work finishes, let's go drinking.

夏休みになったら、海へ行きたいです。

natsu-yasumi ni nattara, umi e ikitai desu.

When summer vacation comes, I want to go to the sea.

[!IMPORTANT] You cannot use 〜たら for habitual actions (e.g., “When I am a child, I played…”). It is used for specific cause-and-effect scenarios or sequential events.

4. Past Discovery (“When I did A, I discovered B”)

There is a less common but important third usage. If the sentence is entirely in the past tense (A〜たら、B(past)), it means “When I did A, an unexpected result (B) happened.”

家へ帰ったら、手紙がありました。

ie e kaettara, tegami ga arimashita.

When I returned home, there was a letter (I discovered it).

窓を開けたら、雪が降っていました。

mado o aketara, yuki ga futte imashita.

When I opened the window, it was snowing (to my surprise).

デパートへ行ったら、休みでした。

depaato e ittara, yasumi deshita.

When I went to the department store, it was closed (unexpectedly).

5. Cultural Insight: Polite Offers with “Yokattara”

One of the most common and useful phrases involving the 〜たら form is よかったら (yokattara), which literally means “If it’s good.” In practice, it translates to “If you like” or “If it’s okay with you.”

Japanese people use this phrase to make offers or suggestions less pushy and more polite. It acknowledges that the other person might be busy or have other preferences.

Common uses:

  • 「よかったら、食べてください。」 (If you like, please eat some.)
  • 「よかったら、明日一緒に映画を見に行きませんか。」 (If you’d like, would you like to go see a movie together tomorrow?)

Using よかったら shows that you are being considerate of the other person’s feelings and situation.

Contextual Dialogues

1. Planning a Trip (旅行の計画)

Listen to how Tanaka and Suzuki plan an outing using both the “If” and “When” meanings of 〜たら.

Planning a Trip (旅行の計画)会話
Tanaka

鈴木さん、明日仕事が終わったら、映画を見に行きましょう。

Suzuki-san, ashita shigoto ga owattara, eiga o mi ni ikimashou.

Suzuki, when work finishes tomorrow, let's go see a movie.

Suzuki

いいですね。もし雨が降ったら、どうしますか。

Ii desu ne. Moshi ame ga futtara, dou shimasu ka.

That sounds good. If it rains, what will we do?

Tanaka

雨だったら、映画の代わりに家でゲームをしましょう。

Ame dattara, eiga no kawari ni ie de geemu o shimashou.

If it rains, let's play games at home instead of the movie.

Suzuki

わかりました。晴れたら、映画館へ行きましょう。

Wakarimashita. Haretara, eigakan e ikimashou.

Got it. If it is sunny, let's go to the movie theater.

2. An Unexpected Discovery (驚いたこと)

Using 〜たら to describe something unexpected.

An Unexpected Discovery (驚いたこと)会話
Suzuki

田中さん、今朝駅に行ったら、先生に会いましたよ！

Tanaka-san, kesa eki ni ittara, sensei ni aimashita yo!

Tanaka, when I went to the station this morning, I met our teacher!

Tanaka

本当ですか？森先生でしたか。

Hontou desu ka? Mori-sensei deshita ka.

Really? Was it Mori-sensei?

Suzuki

はい。話したら、今日は京都へ行くと言っていました。

Hai. Hanashitara, kyou wa Kyouto e iku to itte imashita.

Yes. When I talked to him, he said he's going to Kyoto today.

Tanaka

そうですか。僕も時間があったら、京都へ行きたいです。

Sou desu ka. Boku mo jikan ga attara, Kyouto e ikitai desu.

I see. If I have time, I'd like to go to Kyoto too.

Chapter Summary

Key takeawaysまとめ
  • 1To form 〜たら, take the plain past tense (た/だ) of any word and add ら.
  • 2It can mean 'If [A] happens' for hypothetical situations. (Often paired with もし).
  • 3It can mean 'When/After [A] happens' for guaranteed future events that must finish before [B] starts.
  • 4If used in the past tense, it means 'When I did [A], I made an unexpected discovery [B].'

Knowledge Check

Test your understanding of the 〜たら conditional!

Practice quiz
1 / 15

What is the 〜たら form of the verb '飲む' (to drink)?

Applied review

Use what you learned

Focus: Conditional たら. Try the task before revealing the model.

Guided practice練習

Produce the Japanese sentence, then compare it with the model answer.

  1. 1.Say “When you arrive at the station, call me.”

Reading practice読解

Conditional たら in context

N4 mini-reading

Target: 2 minutes
時間があったら、美術館にも行きたいです。なかったら、駅へ戻ります。
  1. What happens if there is no time?