Final answer:
Bernardo de Galvez's major contribution during the Revolutionary War was capturing New Orleans, Pensacola, and Mobile.
Step-by-step explanation:
Bernardo de Galvez's major contribution during the Revolutionary War was when he attacked and captured British New Orleans, Pensacola, and Mobile. These victories by Galvez helped secure critical ports along the Gulf Coast, cutting off British supply lines and weakening their control in the region. Galveston, however, was not one of the cities captured by Galvez during the Revolutionary War.
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