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GrammarJLPT N5

if / when

と – Conditional 'If / When' (Natural or Automatic Results)

JLPT N5ParticleNeutral
The particle , when used as a conditional, expresses situations where one event naturally, automatically, or inevitably leads to another. It is used for general truths, habitual outcomes, natural consequences, and instructions (such as directions). Unlike たら or , which can express hypothetical or one-time conditions, strongly implies that whenever condition A occurs, result B always or naturally follows. Because of this automatic-result nuance, is generally not used when the result clause expresses the speaker's volition, request, or suggestion — you would not typically follow with commands, invitations, or intentions. The structure is straightforward: attach directly to the plain (dictionary or nai) form of a verb, adjective, or noun + copula. This conditional is extremely common in everyday Japanese for describing how things work, giving directions, and stating scientific or natural facts.

Functions

#1 Natural or scientific consequence

Structure
Verb (dictionary form) + と + Result
はるになるはなきます。

When spring comes, flowers bloom.

Here describes a natural, inevitable consequence: every time spring arrives, flowers bloom. This is a general truth that happens automatically and repeatedly, which is the most typical use of the conditional . The speaker is not expressing a wish or hypothesis but simply stating how nature works.

Structures

Verb (plain form)
Verb (dictionary / nai form) + と + Result clause
い-Adjective
い-Adjective + と + Result clause
な-Adjective / Noun
な-Adjective / Noun + だ + と + Result clause

Common mistakes

A very common mistake is using when the result clause contains a command, request, invitation, or expression of the speaker's will (e.g., してください, しましょう, したい). Since implies an automatic or natural result, pairing it with volitional expressions sounds unnatural — use たら or instead in those cases. Another frequent error is confusing with とき (when); while both can translate as 'when,' emphasizes an automatic consequence, whereas とき simply marks a point in time. Learners also sometimes mistakenly use the ます-form before ; remember that the conditional always attaches to the plain form (dictionary form or ない form), never to the polite form. Finally, some learners overuse for one-time past events (e.g., 'When I opened the window, a bird flew in'), where たら is generally more appropriate unless the speaker is narrating a sequence of discovered results.

Related

たらならとき場合は