There is widespread agreement that certain non-creole vernaculars are

structurally quite different from the languages out of which they grew:

African American English, Afrikaans, Brazilian Vernacular Portuguese,

Nonstandard Caribbean Spanish, and the Vernacular Lects of R´eunion

French. Until now, however, these languages have proved remarkably

resistant to the attempts of linguists to provide a plausible theory to

account for either their genesis or their synchronic structure. Informed

by the first systematic comparison of the social and linguistic facts in

the development of these languages, this book argues that the transmission of their source languages from native to non-native speakers led to

partial restructuring, resulting in the retention of a substantial amount

of the source languages’ morphosyntax, but also the introduction of a

significant number of substrate and interlanguage features. This study

concludes with the proposal of a formal theoretical model identifying

the linguistic processes that lead to partial restructuring, throwing into

focus a key span on the continuum of contact-induced language change

which has not been coherently analyzed up to now. It demonstrates how

the insights gained from the comparative study of such vernaculars cast

much-needed light on the relationship between the diachronic development and synchronic structure of this important group of languages,

with some 200 million speakers.