Modal verbs in TIME: Frequency changes 1923–2006

Between the 1960’s and 1990’s the frequency of modal verbs in the Brown family of corpora fell substantially, a decline which Leech (2003: 96) suggests is indicative of a more “general and long lasting trend”. Taking Leech’s study as a starting point, this paper investigates twentieth century changes in modal verbs using the new and relatively unexplored TIME Magazine Corpus. Results show that while certain modal verbs have fallen in frequency, the overall pattern is one of growth. These changes may be accounted for by the increase of semi-modal verbs and shifts in usage. Results appear to lend support to the explanatory hypotheses of colloquialization, democratization and stylistic change. Investigation of discrepancies between results from the TIME Corpus and the Brown corpora yields important methodological implications. In particular, as a result of sampling variation, a diachronic comparison based on two data points may present an inaccurate picture of the overall trend.