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In page Elena Lieven:

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Her principal areas of research involve: usage-based approaches to language development;[citation needed] the emergence and construction of grammar;[2] the relationship between input characteristics and the process of language development;[2] and variation in children's communicative environments.[2] She has been involved in the design and collection of naturalistic child language corpora initially funded by the Economic and Social Research Council (ESRC) and, more recently, has collected a number of dense databases funded by the Max Planck Institute.