Keiva, most of my students
were mature adults. Most people can't write for peanuts at the best of times. When they are faced with writing a formal dissertation on some subject, their English becomes very stilted. Adult students are also usually ill-educated when they start. If, in the midst of some fairly turgid and convoluted rubbish a stream of well-written prose hits your eye, it's hard not to wonder how come ...
One of the worst offenders I struck was actually a former policeman! He'd be struggling along in his best writing-a-formal-report-on-a-burlary style, then suddenly he'd produce a couple of paras of well thought-out and well-written guff. Then it would be back to the formal police report style. I called him on it and he swore black was white that it was his own work. I found (coincidentally) the passage he'd cribbed a week or so later. When I faced him with it, he nearly broke down in tears.
