A description of the rules for the use of the conversational historical present in American English is given in order to demonstrate the necessity of taking such information into account when applying discourse analysis to second language research. It is argued that native speaker intuition is inadequate as a basis for judging the discourse errors of language learners. A recent study of tense avoidance by Godfrey (1980) is discussed in order to point out the difficulties facing researchers doing pioneering work in the use of discourse analysis for the study of second language acquisition.