Differentiating between a teacher (especially a veteran teacher) and an ambulatory cadaver can be a bit of a problem. Both have a tendency to lurch, both moan incoherently, both are slightly ragged and ill-kempt, and both can be a bit whiffy at times. The important points are to identify possible other reasons for lurching (alcohol, old war wounds, vicious local dogs, confrontations with other teachers), to learn to identify and separate the various natural smells of the teacher (alcohol, dust, must, bad breath and/or armpit odour) and the zombie (rotting flesh), and to learn to differentiate between the habitual moaning of the disillusioned educator and the fiend that feeds on human flesh.