The alternation of high and low tides is caused by the daily (or diurnal) rotation of the earth with respect to these two tidal humps and two tidal depressions.
(The alternation of high and low tides; is caused; by the daily (or diurnal) rotation of the earth with respect to these two tidal humps and two tidal depressions)
The alternation of high and low tides
is caused
by the daily (or diurnal) rotation of the earth with respect to these two tidal humps and two tidal depressions