Final answer:
Children learn new words by following innate linguistic rules, exhibiting overgeneralization, and interacting with their environment. Language development occurs through innate mechanisms, such as the LAD, and learned behaviors supported by reinforcement. Early childhood is a critical period for language acquisition, where children rapidly expand their vocabulary and understanding of language through play and everyday interactions.
Step-by-step explanation:
Children learn new words by following innate language rules that manifest as they grow and engage with their environment. One observable phenomenon is overgeneralization, where children apply a general rule to words that are actually exceptions. For instance, they might say 'gooses' instead of 'geese' because they understand that typically, adding an 's' denotes plurality in English. This indicates their grasp of language rules despite not fully knowing all exceptions.
Language acquisition is partially innate, as argued by Noam Chomsky with his concept of the language acquisition device (LAD), and partly learned through interaction, as supported by B.F. Skinner's reinforcement theory. Starting from a young age, children proceed through different stages of language development, mastering speech by playing, mimicking actions, and responding to their linguistic environment. This capacity is particularly strong during the critical period of early childhood.
By the age of two, children can understand and use a notable amount of words, follow commands, and express a range of actions and emotions through language. Engagement in play and everyday activities, like listening to stories or mimicking adult behavior, significantly contributes to a child's expanding vocabulary and understanding of language rules.