There was a time when a C meant average. The average GPA at four-year colleges and universities has risen from 2.52 in the 1950s to 3.11 in 2006. And according to Stuart Rojstaczer, a former Duke University professor and founder of GradeInflation.com, GPAs only keep rising. At some colleges, Rojstaczer says, over 50% of the grades given are A's.
Trench warfare was caused by an advance in defensive weaponry. The machine gun was too heavy to be used as a mobile weapon, and therefore was placed into a fixed position. Barbed and concertina wire was also heavily used.
Much of the war along the western front was fought using trench warfare. Both sides dug long lines of trenches that helped to protect the soldiers from gunfire and artillery. The area between enemy trenches was called No Man's Land. Trench warfare caused a stalemate between the two sides for many years.