push in

push against an open door

To do something pointless or unnecessary; to try doing something already done.

push it

To make an extraordinary or risky effort; to behave in a way which tests the limits; to take chances; to expect too much.

push on

To persist, persevere.

push one's luck

To take an excessive risk or to attempt some task unlikely to succeed, especially after having already been unexpectedly lucky.

push one's way

to make one's way by pushing.

push the boat out

To do something, especially spend money, more extravagantly than usual, particularly for a celebration.

push the envelope

To go beyond established limits; to pioneer.

push up daisies

To be dead.