Video
Let’s watch this short video for a quick overview.
Source: gokigen japanese official YouTube Channel
Introduction
Want to say “Whenever I drink coffee, I can’t sleep” or “When spring comes, cherry blossoms bloom”? Japanese uses Event A (short [plain] form, present) + と、 Event B to talk about automatic results, laws of nature, habitual actions, or programmed outcomes.
Think of it as the Japanese “whenever/if A, then B (always).” Let’s master the form, its rules, and how it differs from 時 (When Sentence 1, Sentence 2).
1. Structure & Core Meaning
Pattern: Event A [short (plain) / present] + と、Event B
Meaning: Constant condition & result “when A happens, B happens.”
Example: 春になると、桜が咲きます。= When spring comes, the cherry blossoms bloom.
Part | Form | Role | Example |
---|---|---|---|
Event A | short [plain] form, present verb / adj. / noun + と | Cause / trigger | 春になると |
Event B | any tense but usually present | Guaranteed result | 桜が咲きます。 |
2. Conjugation Rules
Word type before と | A-clause form | Example |
---|---|---|
Verb | Dictionary (present) | 雨が降ると … |
い-adj. | Present short (~い) | 暑いと … |
な-adj. | だと | 静かだと … |
Noun | だと | 学生だと … |

A is always present tense, even when both actions happened in the past.
Put と immediately after A; never use に or で here.
3. Example Sentences
Situation | Sentence | Translation |
---|---|---|
Natural law | 春になると桜が咲きます。 | When spring comes, cherry blossoms bloom. |
Habit | かなさんと話すと元気になります。 | Whenever I talk with Kana, I feel uplifted. |
Programmed action | このボタンを押すと電気がつきます。 | If you press this button, the light turns on. |
Automatic feeling | 恥ずかしいと顔が赤くなります。 | When I’m embarrassed, my face turns red. |
Conditional advice | 甘い物を食べすぎると太りますよ。 | If you eat too many sweets, you’ll gain weight. |
Conversations

最近、あまり寝られないんです。
Lately, I haven’t been able to sleep very well.

運動すると、よく眠れますよ。
If you exercise, you’ll sleep better.

すぐ緊張しちゃうんです。
I get nervous really easily.

音楽を聴くと、リラックスできますよ。
If you listen to music, you can relax.
4. Practice Drill
Convert each cue into an A (short/present) + と、B sentence.
Cue | Example Answer |
---|---|
(fall arrives) / trees turn red | 秋になると木が赤くなります。 |
(press switch) / hot water boils | スイッチを押すとお湯が沸きます。 |
(friend doesn’t reply) / feel lonely | 友だちから返事が来ないとさみしくなります。 |
(evening comes) / sky gets dark | 夕方になると空が暗くなります。 |
(run) / lose weight | 走るとやせられます。 |
Challenge: Create two of your own—one natural phenomenon, one habitual routine.
5. Common Mistakes
❌ Wrong | Why | ✅ Fix |
---|---|---|
冬になったと雪がふります。 | A-clause can’t be past. | 冬になると雪がふります。 |
友だちが来たとき、元気になります。 | と expresses constant result; 時 suits one-time event. | 友だちが来ると元気になります。 (if it’s every time) |
Critical Rule: The second clause cannot be your will or command. The most important rule for the A と B pattern is that the result (Clause B) must be a natural, automatic, or uncontrollable outcome.
You cannot use と if Clause B expresses your own intention, desire, hope, command, or suggestion.
- ✅ OK: 春になると、桜が咲きます。 (A natural event)
- ❌ Wrong: 春になると、日本へ行きたいです。 (Your desire/hope)
- Correct version: 春になったら、日本へ行きたいです。
6. Contrast with 時 (A 時、B)
Aspect | A と、B | A 時、B |
---|---|---|
Main use | Constant / habitual / automatic result | Specific time reference (“when A happened, B happened”) |
Tense in A | Always present | Present or past, chosen by relative timing |
Example | 春になると桜が咲きます。= When spring comes, cherry blossoms bloom. | 日本に行った時、桜を見ました。= When I went to Japan, I saw cherry blossoms. |
English cue | Whenever A, B | When A (one time), B |
7. FAQ
- QAre there any rules for the sentence after と? Can I say anything there?
- A
Yes, there is one critical rule. The clause after と cannot express your personal will, desire, command, or suggestion. It must be a natural or uncontrollable result.
- OK:
まっすぐ行くと、右に駅があります。
(If you go straight, the station is on the right. – A fact) - WRONG:
まっすぐ行くと、右に曲がってください。
(If you go straight, please turn right. – A command) - CORRECT WAY:
まっすぐ行ったら、右に曲がってください。
- OK:
- QI saw a sentence like 窓を開けると、雪が降っていた (mado o akeru to, yuki ga futte ita). Why is the second verb past tense?
- A
This is the second key function of
と
: “the discovery pattern.” It’s used when you do action A and, as a direct result, you discover an unexpected situation B.- General Truth:
このボタンを押すと、電気がつきます。
(If you press this button, the light turns on. – It always does.) - Specific Discovery:
家に帰ると、猫がいなかった。
(When I got home, [I discovered that] my cat was gone. – A one-time, surprising event.)
- General Truth:
- QHow do I correctly use a negative verb with to? Is it ~nai to?
- A
Yes, you can use
と
with negative verbs to mean “If X does not happen, then Y is the result.” Simply attachと
to the short-form negative (-nai
).練習しないと、上手になりません。
(If you don’t practice, you won’t get good.)野菜を食べないと
、健康に悪いです。
(If you don’t eat vegetables, it’s bad for your health.)
Be careful not to confuse this with the casual phrase ~ないと (e.g., 行かないと), which is short for ~ないといけない and means “I have to…” or “I must…”.
- QCan と (to) also just mean “and”?
- A
Yes. When used between two nouns, と is the particle for “and.” The grammar is completely different.
- Conditional: 春になると… (When spring comes…)
- Listing Nouns: パンと牛乳 (bread and milk)
- QWhat’s the quick difference between と (to), たら (tara), ば (ba), and 時 (toki)?
- A
to
(と): Automatic Result. If A, then B always happens. Used for natural laws, machine functions, and involuntary habits.tara
(たら): One-Time Condition. “If/After A happens, then B.” This is the most versatile conditional and can be used for almost any situation, including expressing will or commands in the second clause.ba
(ば): Hypothetical/Logical Link. “If A were true, then B would be the logical outcome.” Often used for giving advice. The condition (A) and result (B) must have a logical connection.toki
(時): Time Frame. “When A… / At the time of A…” Focuses on the timing of the action, not the conditional link.
Conclusion
You can now:
- ✅ Form A (short/present) + と、B to express constant results or habitual consequences.
- ✅ Keep A in present tense; add だと for nouns & な-adjectives.
- ✅ Distinguish と from 時 and たら.
Write three new sentences describing natural laws, machine operations, or your own habits—your Japanese will sound clear and logical!