Semantic change in English intensifiers that have developed from a prepositional phrase and a noun phrase

In the advance of research in grammaticalization, there has been some inquiry into the development of English intensifiers. While most studies focus on the process of semantic shift from adverbs or adjectives that are the primary sources of intensifiers, little attention has been drawn to minor members of the category that have developed from a prepositional phrase or noun phrase. However, it is of great interest from the viewpoint of semantic change in general as well as that of grammaticalization and subjectification to examine what factors are engaged in the development of these intensifiers. This paper examines the development of indeed, a lot, a great/good deal, big time and all X wants/likes, and found that such mechanisms as metaphor, metonymy, conversational implicature, reanalysis, and the speaker's intention of producing illocutionary forces contribute to the semantic change of these intensifiers. Furthermore, as a theoretical implication of this study, it is observed that during the semantic shift that is regarded as a case of grammaticalization, most items have undergone subjectification, which gives support to the claim by E. C. Traugott, among others, that subjectification is found to take place concomitantly with