In chapter 3 we pointed out that diglossie speech communities without (individual) bilingualism virtually do not exist. This implies thar in bilingual communities many people have to !earn two languages, particularly those speaking a minority language. In addition to their vernacular they acquire a second language, often the rnajority language or another language of wider communication: a Turkish immigrant worker in Germany leams German, a speaker ofLotuho in Sudan tearus Arabic, a speaker of one ofthe Aboriginallanguages in Australia learns English, etc. Members ofminority groups must attain a certain degree ofbilingualism ifthey wam ro partleipare in mainstream society. Speakers ofa majority language are in a much more comfortable position. If they wish tbey can sray monolingual: Germans generally do net learn Turkish, etc.

In Languages in contact Weinreich (1953) claims thar ‘[rhe] greater the differences between the systems, i.e. the more numerous the mutually exclusive forms and parrerns in eech [language], the grearer is the learning problem and the potential area of interference’ (p. I). Weinreich suggests that the first language influences the acquisition of the second ene. With the term interfermee he refers ra the ‘rearrangement of pattems that results from the introduetion offoreign elements into the more highly srructured domains of language, such as the bulk of the phonemic system, a large part ofthe morphology and syntax, and some areas ofvocabulary’ (p. I).1t is a common-sense notion that secend language learners use elements or structures of their native language in speaking a second tongue: the stereotypie English-speaking Frenchman says ‘I seank’ insteadof'l rhink', beceuse his French phonological system keeps intruding, and the equally stereotypie French-speaking Englishman says: ‘Parlay vuw anglay?'

The influence of one language on the other is extremely important in situations of prolonged and systematic language contact. Here again a quoration from Weinreich is appropriate. ‘In speech, interference is like sand carried by a stream; in language it is the sedimented sand deposited on the bottorn of a lake’ (Weinreieh, 1953: 11). However, the interlanguage of second-Ianguage Ieamers, i.e. their version of the target language, can also be characrerized by ether structural features in addition ra interference, for instanee features due ra simplification oftarget-Ianguage srructures. These features can also become habitualized and established, or - in Weinreich's metaphor - become rhe sedimented sand deposited at the bottorn of a lake.