For bilinguals, the use and knowledge of one language affects how they process the other. Various cross-linguistic influences (CLI) can be observed in both language production and comprehension across all domains of linguistics. We start by broadly exploring the concept of transfer, both negative and positive, and forward and reverse. In doing so, we identify various classifications of CLI. Following this, we review key studies on phonological, lexical, morphological, and syntactic transfer along with other types such as discursive, pragmatic, and sociolinguistic. We find that there are a number of factors that can determine the degree to which transfer emerges or whether it happens at all. We then review studies investigating the ability to switch between the two language systems. In doing so, we look at theoretical models that explain what facilitates language switching and what empirical studies tell us about the neural and electrophysiological activity that arises in language switching. Finally, we discuss dreaming and bilingualism and argue that dreaming in an L2, contrary to popular belief, does not necessarily imply fluency in that language.

This chapter brings together the findings from the three studies, which confirmed that Differential Object Marking (DOM) is a vulnerable grammatical area not only in Spanish, but also in Hindi and Romanian as heritage languages, subject to erosion under pressure from, English in this case. This chapter goes deeper into these overall trends, by comparing the three heritage speaker groups, on the one hand, and the three first-generation immigrant groups, on the other, on several background variables related to patterns of language use. A follow-up replication study with Spanish heritage speakers and immigrants from other countries in Latin America is reported, which confirm the attrition effects in the two generations of Mexican immigrants. It is claimed that his finding is strong evidence that while DOM omission may have started as a developmental outcome of heritage language acquisition, it may be on its way to becoming a stable dialectal feature of Spanish in the United States, suggesting language change with respect to DOM in Spanish. The roles of language internal and language external factors are discussed.

Compared to second language speakers who acquired the language later in life, heritage speakers often show native patterns in many areas of their grammar. Nevertheless, heritage speakers’ ultimate attainment in early adulthood is characterized by significant variability in their overall linguistic proficiency of the heritage language, which often falls outside the range of variation seen in monolingually-raised native speakers. Their native language abilities are dissociated by receptive and productive linguistic skills and within the language modules themselves. This chapter provide examples of the structural changes and differences commonly found in heritage language grammars, compared to the grammars of first-generation immigrants, who speak the same variety as the heritage speakers and who are the most comparable baseline. Heritage grammars are characterized by structural simplification, influence of the dominant language and slow and labored language processing during comprehension and production. Quantity and quality of input may drive processes of language change across generations. Although it has been suggested that changes observed in first-generation immigrants due to attrition are directly transmitted to heritage speakers it is argued that direct transmission from first to second generation is unlikely when considering the interaction of the intensity of the exposure and age of acquisition.

This chapter starts by summarizing the predictions made by various theories of implicature that have consequences for language processing. It then presents empirical evidence bearing on a number of questions related to the processing of implicatures, namely: their processing cost, the difference between particularized and generalized implicatures, the role of mental state attribution for the derivation of implicatures, the role of politeness for the derivation of implicatures.

This chapter discusses the ability of second language learners to derive implicatures. It starts from the observation that Grice’s maxims do not seem to apply in all cultures. These cultural differences explain in part why second language learners experience difficulties with implicatures. The chapter also reviews the roles of other factors, such as the level of linguistic proficiency. The chapter also addresses the main similarities between children acquiring their first language and second language learners. One of the main differences is the existence of language transfer in the case of learners, a notion that is discussed and illustrated with respect to its relation to the phenomenon of implicatures.