sentences:  Each entry lists the general's name, date of rank, active-duty positions held while serving at four-star rank, number of years of active-duty service at four-star rank (Yrs), year commissioned and source of commission, number of years in commission when promoted to four-star rank (YC), and other biographical notes (years of birth and death are shown in parentheses in the Notes column).The modern rank of general was established by the Officer Personnel Act of 1947, which authorized the President to designate certain positions of importance to carry that rank.Officers appointed to such positions bear temporary four-star rank while so serving, and are allowed to retire at that rank if their performance is judged satisfactory.