Complex sentence: The 76 mm Gun M1 was a US WWII tank gun that replaced the 75 mm gun on late M4 Sherman tanks and equipped all M18 Hellcat tank destroyers.
Split into simpler sentences: The 76 mm Gun M1 was a US WWII tank gun. The M1 replaced the 75 mm gun on late M4 Sherman tanks and equipped all M18 Hellcat tank destroyers.