Daily Expression

1. Still working on something
    It means we still doing for something.
    ex:
    A = Have you done your homework?
    B = I am still working on it.

2. I will sleep on it
    It means we still thinking about something.
    ex:
    A = How is your decision?
    B = I will sleep on it.

3. Arm and leg
    It means we must pay something expensively.
    ex:
    A = Your car is good. Is it new?
    B = I pay it with arm and leg.