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Tag - terminology
a mistake vs an error
According to Corder (1967) cited by Ellis (2008), a ‘mistake’ is a deviation in learner language that occurs when learners fail to perform their competence. It is a lapse that reflects processing problems. An error, on the other hand, is a deviation in learner language which results from lack of knowledge of the correct rule (pp. 971, 961).
global errors vs local errors
Global errors are errors that affect overall sentence organization (for example, wrong word order). They are likely to have a marked effect on comprehension (R. Ellis, 2008, p. 964).
Local errors are errors that affect single elements in a sentence (for example, errors in the use of inflections or grammatical functors [sic] (R. Ellis, 2008, p. 970).
Source: Ellis., R. (2008). The Study of Second Language Acquisition. 2nd ed. Oxford: OUP.