Past–future asymmetries in time adverbials and adpositions: A crosslinguistic and diachronic perspective

Expressions like English ago have been claimed to be among the most likely candidates for postposition crosslinguistically, and the reason for this has been conjectured to be diachronic. A few previous contributions notwithstanding, however, we still lack a typologically wider-ranging account of such temporal adpositions and adverbials and of how they develop. These are the main goals of the present article. Relying on a sample of 100 languages, it has been found that: (i) the structure instantiated in English by ago is far from universal and is geographically unevenly distributed; (ii) these expressions are indeed predominantly postposed, which does not hold for their mirror images for the future; and (iii) evidence from etymology, patterns of polysemy, and documented semantic extensions suggests that this asymmetry is the result of past and future markers having different diachronic sources.