Conditionals: 〜たら (~tara)
The ~tara form is the most versatile conditional in Japanese. Depending on the context, it means 'If (A happens), then (B)' or 'When (A happens in the future), then (B)'.
If and When
Unlike English which has different words for 'If' (uncertain) and 'When' (certain to happen), Japanese often uses the exact same grammar: 〜たら.
If the condition is a hypothetical (e.g., If I have money...), ~tara means 'If'.
If the condition is definitely going to happen in the future (e.g., When I arrive at the station...), ~tara means 'When'.
Because of this, ~tara literally translates to 'Upon the completion of A, B will happen.'
How to make the ~tara form
Example Sentences
Teacher's Advice
Why is ~tara based on the PAST tense (ta-form)? Because in the Japanese mind, the second action cannot happen until the first action is COMPLETELY FINISHED in the timeline. 'Arrive-ta-ra' -> Upon the completion of arriving, I will call.
JLPT Exam Patterns
- •Conjugating negative conditions correctly: ~nakattara (N4)
- •Using 'Moshi' (もし) at the beginning of the sentence to emphasize that it's a hypothetical 'If' (N4)
- •Understanding the difference between ~tara (after A happens) and ~te iru aida ni (while A is happening) (N4)
〜たら as a Polite Suggestion
Outside of straightforward conditionals, 〜たら has a very common conversational use that textbooks often skip: gently suggesting something, without the bluntness of a direct command. 早く寝たら？ doesn't literally ask 'if you sleep early, then...'. It means something closer to 'why don't you go to sleep early?' The conditional structure softens what would otherwise sound like an order.
This pattern is everywhere in casual speech: 病院に行ったら？ ('maybe go to the hospital?'), 聞いてみたら？ ('why not just ask?'). Recognizing this use matters for listening comprehension, since if you only know 〜たら as 'if/when,' these suggestions can sound like unfinished sentences rather than complete advice.
Frequently Asked Questions
What is the difference between 〜たら and もし?
もし is not a separate grammar point. It's an optional word that goes at the front of a 〜たら sentence to flag that what follows is hypothetical: もし雨が降ったら、行きません (If it happens to rain, I won't go). You can drop もし and the sentence still works (雨が降ったら、行きません), but adding it makes the 'if' reading unambiguous, which is useful when the same sentence could otherwise be read as 'when.'
Why is the ~tara form built from the past tense (ta-form)?
Because in Japanese, the second event is only relevant once the first one is fully finished: 食べたら (tabetara) literally frames it as 'upon the completion of eating.' This is different from English 'if/when I eat,' which doesn't grammatically mark completion. It's a small structural detail, but it explains why every ~tara form starts from a past-tense base rather than the dictionary form.
Related Grammar
Master Conditionals
Practice converting verbs and adjectives into the ~tara form.