Answer:
The loss of life was greater than in any previous war in history, in part because militaries were using new technologies, including tanks, airplanes, submarines, machine guns, modern artillery, flamethrowers, and poison gas. ... These trenches came to symbolize a new kind of warfare.
The immediate cause of World War I that made the aforementioned items come into play (alliances, imperialism, militarism, nationalism) was the assassination of Archduke Franz Ferdinand of Austria-Hungary. In June 1914, a Serbian-nationalist terrorist group called the Black Hand sent groups to assassinate the Archduke.
When troops went over the top, they usually fixed bayonets and moved out from their trenches in a series of organized waves. ... Once in enemy trenches, fighting became little more than a deadly brawl with soldiers using rifles, pistols, bayonets, trench knives, clubs, and shovels to kill each other.
Step-by-step explanation: