Truscott and Sharwood Smith (henceforth T&SS) propose a novel theory of language acquisition, "Acquisition by Processing Theory" (APT), designed to account for both first and second language acquisition, monolingual and bilingual speech perception and parsing, and speech production. This is a tall order. Like any theoretically ambitious…

A model of language abilities in matrix form is described in which areas of language ability are defined in terms of the effects of receptive and expressive language processes on four linguistic levels: phonology, morphology, syntax, and semantics. (Author)

Research on reading has tried, and failed, to account for wide disparities in reading skill even among children taught by the same method. Why do some children learn to read easily and quickly while others, in the same classroom and taught by the same teacher, don't learn to read at all? In "Language Development and Learning to Read", Diane…