Solution
British commanders had __indeed___ learnt the lessons of the Crimean War, and could adapt themselves to battalion and regimental columns maneuvering in jungles, deserts and mountainous regions; what they failed to ___comprehend____ was that when they came up against the Boers all their tactical and technical skills were of little use because they had __ entirely___ failed to comprehend the trench fighting and ___cavalry__ raids of the American Civil War. In 1899 all arms of the British service went to war with what was to __prove___ antiquated tactics, and in some cases antiquated weapons.