잖아 (jan-a, jana) · 잖아요 (jan-a-yo, janayo) · 거든 (geo-deun, geodeun)
잖아, 잖아요, and 거든 all remind or explain something to the listener, but their usage differs by formality, tone, and context.
One lane per word — no nested boxes, just the gist.
Informal sentence ending used to remind the listener of a fact they already know
When to use
casual talk, reminding info, emphatic rebuttal
The nuance
Used among close friends or informal settings to emphasize or refute information the listener already knows.
Polite sentence ending used to gently remind the listener of known information
When to use
polite speech, gentle reminder, persuasive expression
The nuance
Used in everyday polite speech to gently remind the listener of information they know.
Sentence ending used to explain reasons or conditions, providing information or alerting the listener
When to use
reason explanation, condition setting, starting additional info
The nuance
Used mainly to state reasons or conditions, often followed by further explanation or requests. Can be informal or polite but more common in informal speech.
너 그거 알잖아.
neo geu-geo al-jan-a., neo geu geo al jan a.
Natural informal expression reminding the listener of something they already know among close friends.
너 그거 알잖아요.
neo geu-geo al-jan-a-yo., neo geu geo al jan a yo.
Using 잖아요 in informal speech sounds awkward; 잖아 is appropriate for informal contexts.
그거 재미있잖아.
geu-geo jae-mi-iss-jan-a., geu geo jae mi iss jan a.
Natural informal expression emphasizing known fact among close friends.
그거 재미있잖아요.
geu-geo jae-mi-iss-jan-a-yo., geu geo jae mi iss jan a yo.
Appropriate polite expression to gently remind the listener of a known fact.
늦었잖아! 빨리 와.
neuj-eoss-jan-a! ppal-ri wa., neuj eoss jan a! ppal ri wa.
Natural informal expression emphasizing reason while urging a friend.
늦었잖아요! 빨리 와.
neuj-eoss-jan-a-yo! ppal-ri wa., neuj eoss jan a yo! ppal ri wa.
Sounds unnatural to urge strongly in polite speech; 잖아요 suits gentle reminders.
비가 오거든, 우산 챙겨.
bi-ga o-geo-deun, u-san chaeng-gyeo., bi ga o geo deun, u san chaeng gyeo.
Natural informal expression explaining reason followed by a request.
비가 오거든요, 우산 챙기세요.
bi-ga o-geo-deun-yo, u-san chaeng-gi-se-yo., bi ga o geo deun yo, u san chaeng gi se yo.
Polite expression explaining reason and making a request.
How to politely say '너 그거 알잖아' to a friend?
Which situation fits '거든'?
How to gently remind someone politely of a known fact?
Which is appropriate when strongly rebutting a close friend?
