Final answer:
The Roman Legions adopted the phalanx formation and the tactic of throwing spears before close combat, resulting in highly effective and versatile warfare.
Step-by-step explanation:
The subject of this question is History. The Roman military formations adopted the old Greek phalanx model into the Legion in order to fight on rough mountainous land. This adaptation, combined with the new tactic of Roman soldiers throwing two spears at the enemy before pulling out a short sword and attacking in close combat, had the overall result of making the Roman Legions highly effective and versatile in battle. They were able to hold a strong defensive line with the phalanx formation while also being able to engage in close combat with their short swords.
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