Soldiers can choose to serve again by going through the re-enlistment process.

re-enlistment 是由前缀 re-（表示“再次”）和名词 enlistment（入伍）组成的复合名词。enlistment 来自动词 enlist（入伍、参军），加上名词后缀 -ment 构成。re-enlistment 字面意思是“再次入伍”，指士兵选择延长服役期限或重新加入军队的过程。