Shin and Mill (2021) propose four steps children go through when learning "variable form use." Although I applaud Shin and Miller's focus on morphosyntactic variation, their accrual of evidence is post hoc and selective. Fortunately, Shin and Miller recognize this and encourage tests of their ideas. In support of their work, I share data…

In English, the sentence "Mary didn't eat pizza or sushi" is assigned the "neither interpretation" (both disjuncts must be false). In Mandarin Chinese, the equivalent sentence is assigned the at least one interpretation (at least one disjunct must be false). The cross-linguistic variation in the interpretation of negative…

Ticuna (ISO: tca) is a language isolate spoken in the northwestern Amazon Basin (Brazil, Colombia, Peru). Ticuna has more speakers than almost all other Indigenous Amazonian languages and -- unlike most languages of the area -- is still learned by children. Yet academic linguists have given it relatively little research attention. Therefore, to…

The 'root infinitive' phenomenon in child speech is known from major languages such as Dutch. In this case study, a child acquiring the Papuan language Nungon in a remote village setting in Papua New Guinea uses two different non-finite verb forms as predicates of main clauses ('root' contexts) between ages 2;3 and 3;3. The first root non-finite…

We compare the predictions of two different accounts of first language acquisition by investigating the relative contributions of abstract syntax and input frequency to the elicited production of main and embedded questions by 36 monolingual English-speaking toddlers aged 3;00 to 5;11. In particular, we investigate whether children's accuracy…

This article demonstrates how the Comparative Method can be applied to cross-linguistic research on language acquisition. The Comparative Method provides a systematic procedure for organizing and interpreting acquisition data from different languages. The Comparative Method controls for cross-linguistic differences at all levels of the grammar and…

Most evidence concerning cross-linguistic variation in noun bias, the preponderance of nouns in early expressive lexicons (Gentner, 1982), has come from comparisons of monolingual children acquiring different languages. Such designs are susceptible to a number of potential confounders, including group differences in developmental level and…

The way in which an event is packaged linguistically can be informative about the number of participants in the event and the nature of their participation. At times, however, a sentence is ambiguous, and pragmatic information weighs in to favor one interpretation over another. Whereas adults may readily know how to pick up on such cues to…

Given that L1A of subject properties in non-null subject languages emerges later than that of null subject languages, this study aims at determining to what extent the same pattern of acquisition is observed in early child L2A in bilingual immersion settings where English and Spanish are both source and target languages. Using an elicited oral…

This study investigates how derivational complexity interacts with first language (L1) properties, second language (L2) input, age of first exposure to the target language, and length of exposure in child L2 acquisition. We compared elicited production of "wh"-questions in French in two groups of 15 participants each, one with L1 English…

The article by Amaral and Roeper (this issue; henceforth A&R) presents many interesting ideas about first and second language acquisition as well as some experimental data convincingly illustrating the difference between production and comprehension. The article extends the concept of Universal Bilingualism proposed in Roeper (1999) to second…

Children's production of bare nominals is universal. When acquiring languages disallowing bare nominals, children will develop from the bare to the non-bare stage. However, Mandarin nominals may appear bare or non-bare in various positions with all kinds of interpretations. This dissertation conducts two acquisition studies to examine the…

Research at the interface of bilingual development and child language disorders has increased greatly in the past decade. The purpose of this article is to highlight the theoretical and clinical implications of this research. Studies examining the similarities in linguistic characteristics between typically developing sequential bilingual children…

What makes a child's language development trajectory have the patterns that it has, and what causes differences across children in those patterns? These fundamental questions have for over half a century been at the heart of research on language development in monolingual children, on the cross-linguistic development of language in children from…

The main objective of this paper is to describe the trajectory of Danish children's early lexical development relative to other languages, by comparing a Danish study based on the Danish adaptation of "The MacArthur-Bates Communicative Development Inventories" (CDI) to 17 comparable CDI-studies. The second objective is to address the feasibility…