Compound contributions (CCs) – dialogue contributions that continue or complete an earlier contribution – are an important and common device conversational participants use to extend their own and each other’s turns. The organisation of these cross-turn structures is one of the defining characteristics of natural dialogue, and cross-person CCs provide the paradigm case of coordination in dialogue. This thesis combines corpus analysis, experiments and theoretical modelling to explore how CCs are used, their effects on coordination and implications for dialogue models. The syntactic and pragmatic distribution of CCs is mapped using corpora of ordinary and task-oriented dialogues. This indicates that the principal factors conditioning the distribution of CCs are pragmatic and that same- and cross-person CCs tend to occur in different contexts. In order to test the impact of CCs on other conversational participants, two experiments are presented. These systematically manipulate, for the first time, the occurrence of CCs in live dialogue using text-based communication. The results suggest that syntax does not directly constrain the interpretation of CCs, and the primary effect of a cross-person CC on third parties is to suggest to them a strong form of coordination or coalition has formed between the people producing the two parts of the CC. A third experiment explores the conditions under which people will produce a completion for a truncated turn. Manipulations of the structural and contextual predictability of the truncated turn show that while syntax provides a resource for the construction of a CC it does not place significant constraints on where the split point may occur. It also shows that people are more likely to produce continuations when they share common ground. An analysis using the Dynamic Syntax framework is proposed, which extends previous work to account for these findings, and limitations and further research possibilities are outlined.

Σημαντικές μεταβολές παρατηρούνται τις τελευταίες δεκαετίες στις σχολικές τάξεις της χώρας οι οποίες έχουν διαμορφωθεί με την έλευση πλήθους οικονομικών μεταναστών σχεδόν από όλο τον κόσμο. Από τη συνύπαρξη αυτοχθόνων και αλλοδαπών μαθητών ανακύπτουν διάφορα ζητήματα τα οποία έχουν απασχολήσει προηγούμενες μελέτες και σχετίζονται με την κοινωνική και ψυχολογική προσαρμογή των δεύτερων, την εκπαιδευτική τους πορεία καθώς και τον κίνδυνο εκπαιδευτικής αποτυχίας και κοινωνικού τους αποκλεισμού. Ωστόσο, δεν τίθενται συχνά ερευνητικά ερωτήματα που να εστιάζονται στην κειμενογλωσσική συμπεριφορά των μαθητών/τριών αλλοδαπής καταγωγής στο πλαίσιο της παραγωγής γραπτού μαθητικού λόγου και τη σύγκρισή της με τη αντίστοιχη συμπεριφορά των αυτοχθόνων μαθητών/τριών. Προς την κατεύθυνση προσανατολίζεται η παρούσα έρευνα. / Serious changes are observed the last decandes, since 1990, in the schoolrooms of our country because of the constant inflow of economic migrants. The issue of coexistence of migrants and indigenous pupils is central for a lot of previous studies. In other words are related to the social and phychological adjustment of the later, their educational course and the danger of educational failure. Nevertheless there are not a lot of studies wich focus on the textlingustic options of imigrant male and female students while they are writing an essay and the comarison of these otions to greek stundent's textlingustic behavior. Thiw is exactly the main target of our paper.