Two different topic structures in SOV languages

The main objective of this thesis is to argue that the different topic and focus readings of Korean nun-marked phrases result from structural differences. Korean nun-marked phrases can receive a topic reading a contrastive topic reading and a contrastive focus reading. The topic and the contrastive readings of nun-phrases have been discussed mainly in semantics and pragmatics literature (Büring 2003, etc.). In this research, contrastive topic has been described as focus with topichood. Syntactic research on topic construction has focused on topic studies in operator-movement (Huang 1984, Han 1998) and topic movement to TopP or FocP whose head is nun (Gill and Tsoulas 2004). These focus-oriented studies and movement analyses do not explain why topic and contrastive topic are syntactically different, and why topic sentences do not show a Weak-Crossover effect which results from operator-movement. I show that topic sentences receive different readings due to structural differences. Pro-drop languages like Korean avoid redundancy and drop a pronoun if the meaning is covered by another argument in the same sentence or by discourse. The meaning difference between a topic reading and a contrastive topic reading occurs because the nun-marked phrase can be either merged (for the topic reading) or scrambled (for the contrastive topic reading). Because merging and scrambling are not operator-movement, Weak-Crossover effects resulting from operator-movement do not exist in Korean topic sentences. Contrastive topic readings are made possible due to scrambling, and are not a result of focus movement, a kind of operator-movement. The structural differences among topic, contrastive topic, and contrastive focus in this analysis may apply to other language data, and it is possible to find parallels between topic phrases in Korean and in other languages. For example, left-dislocated phrases are sentence topics in many languages. The left-dislocated phrases may correspond to merged nun-marked phrases in Korean. Resumptive pronouns, which have the same index as the left-dislocated phrases, may correspond to covert pronoun pro in Korean. Analyzing other language data, we may find some kinds of universality in topic and focus structures.