The effect of age of acquisition on ultimate attainment in second language learning has been a controversial topic for years. After providing a very brief overview of the ideas that are at the core of the controversy, I discuss the two main reasons why these issues are so controversial: conceptual misunderstandings and methodological difficulties.…

Some research has posited a natural order of acquisition of English grammatical morphemes common to all learners of English as a Second Language. This meta-analysis investigated whether a combination of five determinants--perceptual salience, semantic complexity, morphophonological regularity, syntactic category, and frequency) accounts for a…

This meta-analysis pools data from 25 years of research on the order of acquisition of English grammatical morphemes by students of English as a second language (ESL). Some researchers have posited a "natural" order of acquisition common to all ESL learners, but no single cause has been shown for this phenomenon. Our study investigated…

Examined the differential role of comprehension and production practice in second language learning. Discusses the results of a study of 82 first-year students of Spanish as a second language that indicated that relative effectiveness of production versus comprehension practice depended on the morphosyntactic complexity of the structure in…

Presents a replication of experiments which found that input practice is better than output practice for comprehension skills, and no worse than output practice for production skills in a second language (Spanish). Findings reveal that these patterns are obscured when the testing time and the morphosyntactic nature of the structure in question…