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'.
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!
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”.
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.
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).
Contextual Dialogue
Let’s see how Tanaka and Suzuki plan an outing using both the “If” and “When” meanings of 〜たら.
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.
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?
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.
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.
はい！じゃあ、駅に着いたら、LINEでメッセージを送りますね。
Hai! Jaa, eki ni tsuitara, LINE de messeeji o okurimasu ne.
Okay! Then, when I arrive at the station, I will send you a message on LINE.
Chapter Summary
- 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!
Quiz
What is the 〜たら form of the verb '飲む' (to drink)?