The main goal of the work in this dissertation is to investigate pre-verbal structure building effects in languages with different configurations such as Spanish, Galician and Basque, by means of using different pre-verbal cues in order to show that syntactic structure can be both interpreted and anticipated before the verbal head.

I examine the syntax of Clitic-Left Dislocations (CLLDs) and other kinds of left-dislocations in Spanish and then analyze their processing. I concentrate on the use of clitic pronouns in Spanish and Galician in CLLD constructions that require the presence of the clitic pronoun to interpret the left-dislocated phrase and where I examine if this left-dislocation is interpreted at the clitic pronoun. Experimental results from three self-paced reading experiments provide evidence that the clitic in these constructions is required and used to interpret the thematic features of the topicalized NP before the verb. Thus, I demonstrate that clitic pronouns are used as pre-verbal cues in parsing and that the active search mechanism is also triggered in long-distance dependencies involving clitic pronouns. I conclude that the active search mechanism is a more general architectural mechanism of the parser that is triggered in all kinds of long-distance dependencies, regardless of whether the search is triggered by gaps or pronouns.

In Basque, verbal auxiliaries overtly encode agreement information that reflects the number of arguments of the verbal head. In negatives, auxiliaries are obligatorily fronted and split from the verbal head with which they otherwise form a cluster. Thus, verbal auxiliaries in Basque are a pre-verbal morphological cue that can assist the parser in predicting structure. Specifically, I examine how predictions for the upcoming structure of the sentence are determined by agreement information on the number of arguments specified in the auxiliary and by the mismatch of this auxiliary with the case features of the NP that follows it. I provide results from a self-paced reading experiment to argue that the parser uses the information encoded in the auxiliaries and demonstrate that the mismatch of the auxiliary with the following NP can prevent the reader from following a garden-path analysis of the sentence.