んだ => Let's... N4
Order
もの/もん/んだもの/んだもん => because; indicates reason/ excuse/ dissatisfaction N3
ふと => suddenly; accidentally; unexpectedly; unintentionally ~ N3
ふしがある => Seem N2
Speculation
ふとした ... => unexpected / incidental / little bitty N2
Expected
~こういうふう => like this N1
Means and methods
なんだか => somehow, somewhat N3
Vague
んだが => Start the story N4
How to say the beginning
んだった => If... (express regret) N2
Regret
べつだんの => particular; special N2
Description
んだか => Confirm and provide information N4
Confirm
とんだ => unthinkable; unimaginable; inconceivable; unexpected N2
Beyond expectations