I am preparing for an employment test at a cadet camp and I have to go through a period of endurance training before hand, to improve my physical shape and to get me used to a military environment. The camp has assigned me a trainer to work with for the next month. In the manual, they suggested that I show a high level of respect for the trainer and refer to him as "sir." The problem is that he is four years younger than me--I'm a 27 year old male and he is a 23 year old guy, so it would feel really awkward. Should I just get over this and refer to him as "sir" automatically when I first meet him, despite the age issue?