Breaking through the threshold in second language free active vocabulary acquisition

Free active vocabulary (FAV) refers to words that can be used automatically by people (Laufer & Paribakht, 1998). FAV is of great significance in second language (L2) study. However, FAV seems to be difficult to be acquired. Even advanced L2 learners' vocabulary use in speaking and writing tends to be limited. As early as in 1991, Laufer (1991) has found that there is a \threshold\" in L2 free active vocabulary development. He found that during learners' study process FAV fails to increase constantly with the growth of L2 proficiency. Observing this phenomenon Laufer (1991) puts forward the \"Threshold Hypothesis\" proposing that L2 FAV would stagnate in L2 learning. The aim of this research was twofold: first to have a deeper understanding of FAV developmental process; secondly if FAV experiences stagnation to find possible reasons for the stagnation and possible ways to tackle the problem. To achieve this research aim four sub-studies were conducted which involved both quantitative and qualitative methods. The first quantitative sub-study is a 12-month longitudinal research. Twenty-seven randomly selected third-year university students whose major was English were observed for 12 months. In the first and twelfth month a composition of about 200 words was collected; meanwhile tests for free active vocabulary passive vocabulary (PV) and controlled active vocabulary (CAV) were conducted. Then all scores of the tests were put into the Statistical Package for the Social Sciences (SPSS) to be analysed. The purpose of this part of study was to obtain details on FAV development and to explore the relationship between L2 learners' free active vocabulary knowledge and other types of vocabulary knowledge. The second quantitative sub-study is a word association research exploring the cognitive mechanism in FAV development. First a group of frequently produced words and seldom produced words were selected. Then word association tests were conducted to explore the lexical networks of the two kinds of vocabulary in the participants' mental lexicon. Their responses to the stimulus words were classified into different categories and the number of responses in each category was counted. Then results were put into SPSS to be analysed. The purpose of the sub-study was to compare the lexical networks of the two types of vocabulary which may shed some light on the lexical construction procedure in FAV development. The first qualitative sub-study is the interview. It aimed to investigate whether students and teachers attached importance to FAV development and whether effective teaching and learning strategies were adopted to promote FAV growth. Possible reasons for FAV stagnation were investigated as well. The second qualitative sub-study is the documentary analysis. The course structure in the period of the 12-month longitudinal sub-study was examined. The English units taken during the period were analysed. The College English Syllabus for English Majors in China was examined as well. The purpose of the documentary analysis was to detect possible factors in course design that may affect FAV development. Results of the sub-studies led to several findings. First it was found that the FAV threshold phenomenon existed when L2 learners reached upper-intermediate to advanced L2 proficiency level. Three features were captured in the threshold phenomenon. The first feature is that the threshold phenomenon is long-lasting; the second feature is that the threshold phenomenon is stubborn‚ÄövÑvp as it does not grow with the growth of PV and CAV; the third feature is that the FAV threshold tends to occur widely as it occurs at most of the word frequency levels. Secondly it was found that both PV and CAV kept growing when L2 learners reached upper-intermediate to advanced proficiency level; FAV was not significantly correlated with PV and CAV in this stage and the gap between PV and FAV and between CAV and FAV became larger. Thirdly there are three tendencies in lexical network construction when a word is developing into FAV. The first tendency is that the word's lexical network tends to be semantised. The second tendency is that some types of nodes tend to increase in the process while other types of nodes tend to decrease; and they change at different speeds. The third tendency is that the connections of the lexical network tend to get stronger and tighter. In summary the lexical network tends to develop in a way that the word becomes easier to be accessed activated and retrieved. Fourthly it was found that there were possible factors for FAV stagnation in both teaching and learning. In teaching the first factor is that teachers seem not to have given adequate attention to FAV in classroom instruction. The second factor is that little effort has been made to facilitate students in FAV development. The third factor is that there are inadequate units for output training in the curriculum. In learning there are several possible factors for FAV stagnation as well. The first factor is that students' effort to improve FAV may not be enough as the strategies they adopted were rather limited; sometimes the effort was not persistent as it was given up later. The second factor is that there is insufficient intentional learning in FAV study. Lastly some effective teaching and learning strategies were detected from the research. The learning strategies include sentence making with the target word note-taking on the target word putting down example sentences collecting synonyms etc. The effective teaching strategies include providing synonyms of the target word negotiating word meanings analysing the word's contexts encouraging students to make sentences with the word and raising students' attention to the word. In general the research aim was fulfilled."