ㄐㄧㄢˋㄐㄧㄒㄧㄥˊˋjiànjī‑xíngshì

见机行事
  1. 看準時機立即行動根據實際情況靈活變通 腦子靈活見機行事完成」。

see the opportunity and act (idiom)​; to act according to circumstances, to play it by ear, to use one's discretion