to find the real reason or cause of something
物事の本当の理由や原因を突き止める (monogoto no hontou no riyuu ya genin o tsukitomeru)
"Let’s get to the bottom of it before making any decision."
"決定を下す前に、その本当の理由を突き止めましょう。" (kettei o kudasu mae ni sono hontou no riyuu o tsukitomemashou)
to secure something so it cannot change
to sit down and relax, especially after working hard
to have the mindset that you are capable of doing something
in a risky or dangerous situation
to be in charge of something or to be responsible for it
A family member or close relative.
