In the U.S. Marine Corps, candidates for Drill Instructor Duty are primarily volunteers. The tour of duty is three years and is widely regarded as one of the most .\r<br>\r<br>In the U.S. Marine Corps, candidates for Drill Instructor Duty are primarily volunteers. The tour of duty is three years and is widely regarded as one of the most .\r<br>\r<br>In the U.S. Marine Corps, candidates for Drill Instructor Duty are primarily volunteers. The tour of duty is three years and is widely regarded as one of the most .
