Final answer:
Washington's greatest challenge at Valley Forge was keeping the Continental Army together amidst harsh conditions and low morale.
Step-by-step explanation:
During Washington's winter at Valley Forge, his greatest challenge was indeed keeping the Continental Army together. The soldiers faced harsh conditions, including a lack of supplies, disease, and starvation. Many soldiers deserted, and the morale was low. However, Washington's leadership and the assistance provided by Friedrich Wilhelm von Steuben helped to improve the situation and transform the Continental Army into a professional force capable of standing up to the British.
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