Complex sentence: The 75mm Pack Howitzer M1 (redesignated the M116 in 1962) was designed in the United States in the 1920s to meet a need for an artillery piece that could be moved across difficult terrain.
Split into simpler sentences: The 75mm Pack Howitzer M1 (redesignated the M116 in 1962) was an artillery piece used by the United States. It was designed in the 1920s to meet a need for a howitzer that could be moved across difficult terrain.