Infants from low-socioeconomic status (SES) households hear a projected 30 million fewer words than their higher-SES peers. In a recent study, Hirsh-Pasek et al. (Psychological Science, 2015; 26: 1071) found that in a low-income sample, fluency and connectedness in exchanges between caregivers and toddlers predicted child language a year later…

The current project longitudinally investigated the extent to which first-year Japanese university students developed their second language (L2) oral ability in relation to increased input in foreign language classrooms. Their spontaneous speech was elicited at the beginning, middle and end of one academic year, and then judged by linguistically…

This article reports results of a longitudinal study of vocabulary breadth knowledge growth, vocabulary fluency development, and the relationship between the two. We administered two versions of the Vocabulary Levels Test (VLT; Nation 1983; Nation 1990; Schmitt et al. 2001) to 300 students at a Chinese university at three different time points…

In the seven decades since Leopold's groundbreaking 1939 study, there has been no longitudinal study covering more than two years of a Japanese bilingual subject's development. Despite the lack of longitudinal research, however, we have been broadly informed by the veritable outpouring of research on a short-term basis since the late twentieth…

Lexical proficiency, as a cognitive construct, is poorly understood. However, lexical proficiency is an important element of language proficiency and fluency, especially for second language (L2) learners. Lexical proficiency is also an important attribute of L2 academic achievement. Generally speaking, lexical proficiency comprises breadth of…