Double-take, # 208

Via Dr Faustus, and not a very promising start:

Source: Catrine Carpenter, Teach Yourself: Beginner’s French (London: Hodder Headline, 2003), p. vii

In addition to the overlooked duplication, the sentence includes a unhappy choice of lexis: an if where, as Cambridge Dictionaries Online confirms, the preferred conjunction in a situation offering alternatives linked with or is whether.

course course; if … or