The present study is based on a MA thesis submitted to the council of College of Education, Ibn Rushd, University of Baghdad, Iraq in 1989 for the degree of master of Arts in English Language and Linguistics. It describes the syntactic and semantic aspects of adverbial clauses and phrases of reason through which the English language mainly expresses the idea of causality. Furthermore, it presents the general points of causality as a philosophical context. A short review of the traditional treatment of causality is given at first, followed by the transformational treatment. It derives some rules that transform kernel sentences into adverbial clauses and, if possible, phrases of reason having the same meaning and embed them within a matrix sentence.
