Final answer:
The French helped the colonists fight the British because they saw an opportunity to weaken Britain and gain an ally. The colonial victory at Saratoga convinced the French that the colonists could win.
Step-by-step explanation:
The French decided to help the colonists fight the British because the colonial victory at Saratoga convinced them that the colonists could win. The French saw this as an opportunity to weaken their long-standing enemy, Britain, and gain an ally in the American colonies. Their support came in the form of military aid, supplies, and troops, which proved crucial to the eventual success of the American Revolution.
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