To walk out on somebody / something =1. To leave your husband, wife etc. Suddenly.
(ترک کردن ناگهانی همسر)
2. To stop doing something you have agreed to do.
Without further ado = without delaying or wasting any time.
(بدون اتلاف وقت)
Call it a day / a night = to decide to stop working, especially because you have done enough or you are tired