Historical Linguistics and Language Families 10, Exercise 2: sorting resemblances

ten / decem                       inheritance: a regular correspondence
                                  (English t- matches Latin d-)
day / dies                        chance: they match, but the source calls it
                                  chance
taboo / Polynesian                borrowing: English taboo was borrowed from
                                  Tongan
Armenian and Iranian words        borrowing: so many that Armenian was at first
                                  thought a divergent Indo-Iranian branch
Balkan avoidance of the           contact: a sprachbund feature shared by
infinitive                        languages in contact, including Turkish, which
                                  is not Indo-European

Sources: Chapters 3, 6 and 9, from Wikipedia's articles on the comparative
method, language contact and linguistic area.