Final answer:
Enlisted personnel advance through their paygrades by gaining promotions based on years of service, performance evaluations, and completion of required training.
Step-by-step explanation:
Enlisted personnel in the military advance through their paygrades by gaining promotions based on their years of service, performance evaluations, and completion of required training. For personnel with a paygrade of E-4 through E-7, advancement is typically based on a combination of factors including time in service, job performance, and passing exams or meeting specific criteria for each rank.