-다시피 vs -잖아요: Shared Ground, or You Already Know

The holiday everyone knows

You are writing a note, or speaking to a room that already has the calendar.

알다시피 내일 휴일이에요.
aldasipi naeil hyuirieyeyo — As you know, tomorrow is a holiday.

다시피 opens shared ground. 알다, 보다, 느끼다 like this seat: 보다시피, 느끼다시피. The fact is presented as already in the room. No prod.

Swap the ending.

내일 휴일이잖아요.
naeil hyuirijanayo — Tomorrow is a holiday — you know that.

잖아요 treats the fact as something they already have, or should accept. Friends use it as a light reminder. Aimed at a senior about their own slip, the same mark can sting. 알잖아요 내일 휴일이에요 as your first line to a manager is the wrong opener. It is not a polite 알다시피.

I already told you

Same clock, two seats.

일곱 시에 온다고 말했잖아요. You already said the time. The reminder sits on 잖아요. It can stay warm with a friend. It can sound like a score-settling if you aim it up.

알다시피 일곱 시예요 is a heavier shared-ground line. Fine in a written brief. Odd as a nudge to someone who just forgot. Do not reach for 다시피 because it looks more textbook-kind.

Almost, and the room

다시피 has a second job: 죽다시피 일했어요 — you practically worked yourself dead. That is not this contrast. Do not drag 잖아요 onto that almost-sense.

The test on this page is one room. Are you laying a fact down as common ground? 다시피. Are you reminding them they already know, and risking heat if you aim it up? 잖아요. 늦었잖아요 to a senior about their delay is the failed line this page exists to mark. 보다시피 문이 닫혀 있어요 can stay calm in a note: as you can see. 문 닫혔잖아요 to the person who left it open is the reminder, and it can heat. Friends can still hear 알잖아 as a light nudge. The same syllables aimed up are the ones that sting. Do not leave thinking both are fine if you add 요. The letters share a “you know” gloss in English. The seats do not.