Speakers display considerable variability in language use and representations: they may have different pronunciations of the same word, different intended meanings for the same phrases, and different sets of syntactic constraints in their internalized grammars. Comprehenders adapt to such variability by constantly updating their expectations for…

Aspectual and mood morphology are vulnerable domains in adult heritage speakers. This paper investigates the root of such vulnerability within the domain of Turkish evidentiality system by comparing 20 second-generation adult and 20 school-age child Turkish heritage speakers to 20 first-generation immigrants (main input providers for child…

Bilinguals are able to compose expressions across their languages with seeming ease. This phenomenon, commonly referred to as "code-switching," has challenged both theoretical models in linguistics as well as neurobiological models of language processing. And yet, our models of the bilingual brain and the language processing mechanism…

We investigated whether children's inhibitory control (IC) is associated with their ability to produce irregular past tense verb forms as well as learn from corrective feedback following overregularization errors. Forty-eight 3;6 to 4;5 year old children were tested on the irregular past tense and provided with adult corrective input via models of…

This mixed methods study draws upon theoretical perspectives from usage-based linguistics (UBL) and variationist sociolinguistics to explore four learners' use of second language (L2) Spanish present tense indicative verbal inflectional morphology (i.e., simple present conjugations). The study compares the frequency and distribution of students'…

We investigated whether the accuracy of grammatical morphemes in second language (L2) learners' writing is associated with usage-based distributional factors. Specifically, we examined whether the accuracy of L2 English inflectional morphemes is associated with the availability (i.e., token frequency) and contingency (i.e., token frequency…

This study is a replication and extension of Morgan-Short et al.'s (2018) investigation into the role of attention in input processing by L1-Polish learners of L2-Spanish, with proficiency and language of assessment explored as two key methodological factors. Our aims were twofold: to investigate learners' comprehension in different conditions…

As a public compulsory course for Non-English majors in colleges and universities, College Public English should not only develop students' language and cross-cultural communication skills, but also cultivate their correct outlook on life, values, world and native land emotion, which is consistent with the ideological-political goals of the…

When linguistic input contains inconsistent use of grammatical forms, children produce these forms more consistently, a process called "regularization." Deaf children learning American Sign Language from parents who are non-native users of the language regularize their parents' inconsistent usages. In studies of artificial languages…

Complex systems of inflectional morphology provide a useful testing ground for input-based language acquisition theories. Two analyses were performed on a high-density (12%) naturalistic sample of two Polish-English children's (2;0 and 3;11) and their parents' use of Polish noun inflection: first, each child's use of inflectional affixes and their…

This paper revisits the longstanding observation that children produce modal verbs (e.g., must, could) with their root meanings (e.g., abilities, obligations) by age 2, typically a year or more earlier than with their epistemic meanings (e.g., inferences). Established explanations for this "Epistemic Gap" argue that epistemic language…

The English past counterfactuality is difficult for non-native learners to learn and understand due to cross-language discrepancies. Oftentimes, individuals unavoidably develop the interlanguage and this language system becomes fossilized regardless of the amount of exposed time and input. The purpose of the study was twofold: (a) to examine 126…

The "wanna" facts are a classic Poverty of Stimulus (PoS) problem: "Wanna" is grammatical in certain contexts ("Who do you want PRO to play with?") but not others ("Who do you want who[strikethrough] to play with you?"). On a standard analysis, "contraction" to "wanna" is blocked by some…

The cross-categorical use of nouns and verbs poses a challenging problem to young language learners because they are known to be less willing to accept that a single form of a word be used for more than one linguistic purpose (e.g., one-form/one-function principle). The present study investigated whether children under 3 years of age are able to…

Early trilingual development is an excellent testing ground for input reduction effects on acquisition outcomes. This article reports a study investigating input-outcome relations in a child Leo in Hong Kong, who was addressed to in Mandarin, Cantonese and later also in English by caretakers through 'one caretaker-one language' and 'one day-one…