Tendon is the pattern where a line or an event that landed once is brought back and delivered again — after leaving a gap.
The first delivery does not have to be funny. Its job is to put something in the room’s memory. The second delivery collects it. What produces the laugh is the sensation of return: oh — that again.
Oyakusoku — literally “the promise” — is the standard, well-worn development for a situation, carried out exactly as everyone expected. In Japanese it is also called beta: the stock version, the obvious one, the move you can see coming from a long way off.
Two words first, because everything here is built out of them. In Japanese comedy the boke is the one who says the wrong thing, and the tsukkomi is the one who corrects it — the word covers both the person and the act. In a two-person routine those are conventionally separate jobs, held by different people — acts that blur the two, or swap them mid-routine, do exist.
You are watching a Japanese show with subtitles. You follow every line. And then a character says something completely ordinary — and everyone laughs. Or another character shouts a single word and the scene is over, and you can tell that was the joke, but not why.
Gap is the pattern where an impression that already exists — built by appearance, by rank, or by how someone usually behaves — is contradicted at exactly one point.
The department head with the hard face, the one everybody quietly assumes writes in clipped functional sentences. Then his message arrives and it is wall-to-wall emoji.