Contrastive Analysis involves comparing features of one language against another. For example a contrastive analysis of the structures of English and Italian might note that both languages possess the equivalent structure have/avere (auxiliary verb) + past participle, but that the use of the structure differs - in English to express time anterior to a specific moment (eg I've lived here for five years = before now / I'll do it after I've talked to John = talking to John must happen before I do it) while in Italian Ho visto Elena ieri expresses a past event - ie I saw Elena yesterday. Similarly a contrastive analysis of the pragmatics of English and Polish would point to a difference in the formulations of functions such as requests, invitations and advice - Polish using far more direct forms (Sit! / You must have some more / I advise you to... ) than the more tentative English :Would you like to sit down? Are you sure you don't want any more? / Why don't you... (Wierzbicka, A. 2003).
Contrastive Analysis arose from structural linguistics and, though largely focusing on phonological, lexical and structural features, was used to predict error - error being seen as a matter of first language (L1) interference. Later work on error analysis by linguists such as Pit Corder (1981) showed that this view was too simplistic. There were other reasons for error, for example overgeneralisation, which were unconnected to the L1, and transfer between languages could be positive as well ans negative. However, I would argue that contrastive analysis still has a role to play in course design or lesson planning. Lennon (n.d) summarises the work of Lado (1957), who pointed out :
... it is possible to identify the areas of difficulty a particular foreign language will present for
native speakers of another language by systematically comparing the two languages and cultures. Where
the two languages and cultures are similar, learning difficulties will not be expected, where they are
different, then learning difficulties are to be expected, and the greater the difference, the greater the degree
of expected difficulty.
This type of analysis therefore has obvious implications for course design and lesson planning. if we know where important differences between our learners' L1 and the target language (in our case English) lie, then we can plan our courses so that more time is spent on these and less on those which the learners will find easier. This is clearly easiest when teaching monolingual classes, but even with multilingual groups, if the teacher notices that a particular learner is having greater difficulty with a certain area than other members of the group, research into his/her L1 will often provide the explanation and show the teacher how best to help the student.
(1957) Linguistics across Cultures, University of Michigan Press
Lennon, P. Contrastive analysis, Error Analysis, Interlanguage
Pit Corder, S. 1981, Error Analysis and Interlanguage, Oxford university Press
Wierzbicka, A. 2003 Cross-Cultural Pragmatics: The Semantics of Human Interaction Mouton de Gruyter