In a nutshell, the Earth's rotation is slowing due to the friction between the ebb and flow movements of the tides and the seabed.
Some may ebb and flow.
His subtle shifts of tone, the ebb and flow of anxiety.
Migration waves began to ebb and flow in concert with international conflicts and civil wars: Lebanon.
But how can a teacher tell, given the great ebb and flow of emotion, the daily dramas that enfold children's lives.