Diachronic processes and synchronic degree of Grammaticalization of English Causal Complex Prepositions

This paper provides a detailed description of grammaticalization of causal complex prepositions because of, by reason of, due to, owing to, and thanks to, and explores the degree of grammaticalization of the causal prepositions. This study investigates the morphosyntactic changes occurring in the evolutionary process of causal complex prepositions from different source lexemes. The core mechanism by which the structural change takes place is analogy. This study provides strong evidence that analogy creates a grammatical category in contrast to the previous claims that only reanalysis can form a grammatical structure. In addition, the degree of grammaticalization of the causal complex prepositions is measured in terms of morphosyntactic parameter and parameter of age-of-grams. This study shows that the more cohesive a complex preposition is, the more grammaticalized it is, and semantically older grams tend to be more grammaticalized than younger ones. Given these two parameters, the causal complex prepositions can be put on the degree of grammaticalization in increasing order: due to, thanks to, owing to, by reason of, and because of.