〜と
Whenever… then… (natural-consequence conditional)machine translation
FormationVerb dictionary form / ない-form + と; adjectives and nouns in plain present form + と
と links two clauses in a "whenever A, B is certain to follow" relationship: as soon as condition A occurs, result B automatically follows. That's why と is the go-to for how machines work (press the button and a ticket comes out), giving directions (go straight and you'll see the bank), natural phenomena (when spring comes, the flowers bloom), and repeated habits. The first clause is always in plain present form, even when the whole sentence narrates the past.
An important restriction: the second clause of と cannot contain intentions, commands, invitations, or requests. You can't say ×春になると、花見に行きましょう — when you want to invite, order, or ask someone to do something, you must switch to たら or ば.
Among the four N4 conditionals, と is the most "automatic." たら is far more flexible: it works for one-time events and its second clause is completely unrestricted; ば puts the emphasis on the condition itself, suiting general hypotheticals; and なら takes off from a topic the other person just raised. If B is not the natural consequence of A, don't use と.
Examples
このボタンを押すと、切符が出ます。
When you press this button, a ticket comes out.
春になると、桜が咲きます。
When spring comes, the cherry blossoms bloom.
この道をまっすぐ行くと、右に銀行があります。
If you go straight down this street, there's a bank on the right.