There are five verbs in present-day English that indicate the apparentness of a subsequent finite subordinate clause: seem, appear, look, sound, and feel. These verbs can be linked to the lower clause by one of five comparative complementizers: as if, as though, like, that, and null. Although like is the newest of these variants (López-Couso and Méndez-Naya 2012:177), it is overwhelmingly the predominant one in vernacular Canadian English and as if and as though have become negligible (López-Couso and Méndez-Naya 2012:185). I investigate this rapid lexical replacement with the use of two corpora: the Toronto English Archive (Tagliamonte 2003-2006) and an earlier collection of Canadian writing, drawn from Project Gutenberg Canada, primarily representing the decades between 1860 and 1930. The Toronto data shows a change in apparent time whereby like is overtaking the two remaining variants, that and null. In the earlier written materials, there are only 18 tokens of like, but all of these are in fictional dialogue written to come across as nonstandard; this suggests that like was known as a highly colloquial comparative complementizer until it started catching on across registers. The literality of the subordinate clause proves to be a key aspect of the change: in the earlier material, as if and as though are more likely with fully metaphorical subordinate clauses, that and null more often introduce the concrete ones, and like does not exhibit a clear preference. This semantic conditioning is stable over real time between 1860 and 1930, implying that one advantage that like has had over its moribund competitors is its versatility as far as literality is concerned.
"Comparative Complementizers in Canadian English: Insights from Early Fiction,"
University of Pennsylvania Working Papers in Linguistics: Vol. 20
, Article 2.
Available at: http://repository.upenn.edu/pwpl/vol20/iss2/2