Explanation:

The permanent tilt of the Earth’s axis and the revolution of the Earth in its orbit together causes varying length of day and night at different time of the year.

The change between day and night is caused by the rotation of the Earth on its axis. If the Earth did not rotate as it does, the day/night cycle would be very different or possibly even nonexistent. The changing lengths of days and nights depends on where you are on Earth and the time of year.