The correct answer to this open question is the following.
During World War I, a stalemate was the term widely used to describe a state of war in which neither side was winning or gaining an advantage.
This happened during the war in the trenches in WW 1.
The adaptations that the solders made for fighting in the trenches during World War 1, allowed the troops to modify the strategy when they built the trenches in the war front. The trenches were built to protect soldiers from firearms from the enemy. The strategy used prolonged the war in what historians call "a stalemate in the Western Front," from 1914 to 1918. During this period, there were no significant advances on both sides.