が最後 (ga saigo)
Meaning: once something occurs; something else happens
How to use the: Verb-casual, past + が最後/ら最後
Explain:
The latter is a sentence indicating the speaker’s will or state that will inevitably occur.
Example sentences:
1, ここで会ったが最後、謝ってもらうまでは逃がしはしない。
Koko de attaga saigo, ayamatte morau made wa nigashi wa shinai.
Once I see you here, I definitely won’t let you escape until you apologize to me.
2, この計画を聞いたが最後、あなたもグループに加わってもらおう。
Kono keikaku o kiitaga saigo, anata mo gurūpu ni kuwawatte moraou.
If you have asked about this plan, we definitely must invite you to join.
3, 不倫をしたが最後、なかなか元の家庭に戻れない。
furin o shita ga saigo, nakanaka moto no katei ni modorenai.
Once you commit adultery, your family will never be the same again.
4, 学校内でタバコを吸っているのを見つかったが最後、停学は免れないだろう。
Gakkō-nai de tabako o sutte iru no o mitsukatta ga saigo, teigaku wa manukarenaidarou.
If caught smoking in school, it is inevitable that the school will be suspended.
5, あの子はいったんに遊びに出たが最後、暗くなるまで戻ってこない。
ano ko wa ittan ni asobi ni deta ga saigo, kurakunaru made modotte konai.
Once that child goes out to play, he won’t return until late at night.