～としたら／～とすれば／～とすると — Assuming That
Used to set up a hypothetical or assumed premise and then reason about its consequences: 'if we assume ~, then...'. Unlike simple conditionals, these focus on logical deduction from a supposition. としたら and とすれば are largely interchangeable; とすると leans toward a natural conclusion that follows automatically.
Structure
[Plain form / Noun / adj] + としたら／とすれば／とすると
Examples
彼の話が本当だとしたら、大変なことになる。
Kare no hanashi ga hontou da to shitara, taihen na koto ni naru.
If we assume his story is true, this is going to be serious.
としたら sets up the premise ('his story being true') to reason forward.
今から出発するとすれば、何時に着きますか。
Ima kara shuppatsu suru to sureba, nanji ni tsukimasu ka.
Assuming we leave now, what time will we arrive?
とすれば supposes a condition and asks about the resulting outcome.
この道が正しいとすると、駅はもうすぐだ。
Kono michi ga tadashii to suru to, eki wa mou sugu da.
If this road is right, then the station is close.
とすると draws the natural conclusion that follows from the assumption.
• Emphasis is on supposition + reasoning, not on real conditions. • とすると often introduces a conclusion that logically/naturally follows. • Register: neutral; common in both discussion and writing.
Commonly confused with
The JLPT rarely asks whether you recognise a pattern — it asks which of several similar patterns fits. These are the ones ～としたら／～とすれば／～とすると is tested against.
vs ～なら
なら responds to a topic just raised ('if that's the case'), while としたら explicitly frames a hypothesis to reason from.
vs ～たら
Plain たら often means 'when/after' a real sequence, whereas としたら stresses an assumed premise ('supposing that').
More conditionals
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