| This dissertation examines syntactic constructions involving English impersonal verbs from both synchronic and diachronic perspectives. Those are impersonal, causative and personal constructions, which are further subdivided into nine types. In addition, the Dummy-Construction and the Subject Equi-NP Deletion and Subject Raising constructions are examined. The basic method is a particularistic approach by which each verb is separately examined, for only such an approach can provide us with the actual syntactic facts of these constructions in each synchronic stage, and these facts in turn allow for a true explanation of the diachronic changes involved.;I find that the syntactic types of impersonal verbs are heterogeneous across the verbs in each synchronic stage and the relevant syntactic changes are gradual. These findings cause problems for same generative accounts which pursue overarching cross-lexical generalizations.;Yet, some main tendencies are also observed. Between OE and ME more varieties of personal subtypes are observed over time, while impersonal constructions become lost and die out by the sixteenth century. The Prototypical Subject Requirement constraint is proposed as a trigger for such changes.;Even though many previous works have treated a dative Experiencer as an object, the dative Experiencer in the impersonal construction with two noun phrases is found to have syntactic properties. Such subjecthood of the Experiencer, though not prototypical, is a forerunner of the subsequent change toward personal constructions. When a verb takes a clausal complement, the patterns for the introduction of a Dummy-Construction are explored, since such an introduction is not cross-lexical. This study proposes two syntactic conditions as requirements for a verb to develop a Dummy-Construction. All these individual changes are explained by reference to the same underlying causation, namely the Prototypical Subject Requirement constraint. To support the claim that this language-specific constraint is a well-motivated underlying force for English, independent evidence is provided. Moreover, it is shown that the mechanism of Reanalysis played an important role by introducing an innovative construction that rivals the old one, which had the potential for multiple analyses, and eventually leads to the demise of the old structure. |
