The LTE group focuses on the study of what we know when we know a language, that is, how knowledge of language is represented in the mind of the individual and which mechanisms are involved in language production and comprehension. Its main research interests are models of the architecture of grammar, examined in terms of their psychological reality, the processes involved in native and nonnative language acquisition and the modelling of intra and cross-linguistic variation. The group associates work on formal grammar with a varied empirical basis drawn from different methodologies of data collection: corpus data, judgement data and ellicited production and comprehension data. The group members are organized around specific topics in the fields of syntax, semantics, morphology, phonology and phonetics, which are studied in different populations (native speakers, early and late L2 acquirers, heritage language speakers).The group is actively engaged in the training of junior reseachers by integrating them in research projects and organizing seminars and graduate student meetings. There is strong articulation with other national and international research centers, by means of joint projects and the organization of events. Current partnerships include, among others, the Linguistic Centers of Porto and Lisbon, the Language Processing Laboratory of the Federal University of Paraíba, and the Faculty of Modern Languages, University of Frankfurt.