Incidental vocabulary acquisition: The effects of task type, word occurrence and their combination

We investigated how long-term retention of new words was affected by task type, number of word occurrences in the teaching materials and the combination of the two factors. The tasks were: reading a text with occasional Focus on Form when learners used dictionaries (T+F), or reading a text with Focus on Forms, i.e. word focused exercises (T+Fs). The words occurred 2-3, 4-5, and 6-7 times. Consequently, there were six conditions that reflected the 2 × 3 'task × occurrence' combinations. Learners were exposed to 60 target words, 10 words in each condition during a 13-week course of study, and were subsequently tested on them by two unannounced tests: passive recall and passive recognition. An increase in word occurrence was found to have an effect on retention in T+Fs only. Starting with 4 occurrences, T+Fs fared better than T+F. Task type effect was superior to the effect of word occurrence in recall only (2 word exercises fared better than 6-7 occurrences in text). The value of word-focused practice was also confirmed by learners' responses to an introspective questionnaire.