1st Lt. Bill Lining, fire team leader, practices squad movements during a field exercise at Range 5 aboard Marine Corps Base Quantico on March 21, 2014. The Basic School Marines will conduct four field exercises before graduating the six-month course. - 1st Lt. Bill Lining, fire team leader, practices squad movements during a field exercise at Range 5 aboard Marine Corps Base Quantico on March 21, 2014. The Basic School Marines will conduct four field exercises before graduating the six-month course.