This chapter deals with the review of the related literature. In the first section, vocabulary learning strategies and its theoretical framework will be reviewed. For the second section the related research both international and national will be presented.
2.2. Vocabulary learning strategies
Vocabulary learning strategies can be considered as a part of general learning strategies in second language acquisition. The first development in learning strategies area began in 1970s with research to recognize the characteristics of good language learners (Naiman et al., 1978; Rubin, 1975). O'Malley and Chamot define learning strategies as "the special thoughts or behaviors that individuals use to help them comprehend, learn or retain new information" (1990, p.1). This definition can be seen in Schmitt's defining vocabulary learning strategies too. Schmitt says learning is "the process by which information is obtained, stored, retrieved and used... therefore vocabulary learning strategies could be any which affect this broadly defined process" (1997, p.203). This definition brings this question to the mind that whether vocabulary learning is incidental or deliberate, a factor which researchers have discussed in the literature a lot. Nation considers vocabulary learning as a deliberate process which possesses intentional character. He established his description on the properties and qualities of a strategy which fulfills teacher's aims.
Call for helping learners improves the way they go about learning vocabulary have been made on a number of grounds. Sokmen (1997, p. 225) argues in order to help learners learn how to acquire vocabulary by them self, noting that it is "not possible for students to learn all the vocabulary they need in the classroom". Cunningsworth (1995, p. 38) gives a name to helping learners make their own vocabulary learning strategies which is "a powerful approach", that can be based on being sensitive to vocabulary systems, encouragement of sound dictionary skills and showing reflection to useful learning techniques. By considering the importance of vocabulary learning strategies, it would be very helpful to study about these strategies and find out what they are and examine how these strategies are going to help learners for building their vocabulary and also what strategies would be useful for the learners to be introduced in the textbooks.
Brown and Payne (1994) found these five steps in the process of vocabulary learning in a foreign language: (a) having sources for encountering new words, (b) getting a clear image, either visual or auditory or both, of the forms of the new words, (c) learning the meaning of the words, (d) making a strong memory connection between the forms and the meanings of the words, and (e) using the words.(cited in Gani Hamzah et al., 2009, p.42) Following as a result, all vocabulary learning strategies, totally or partially, should be related to these five steps (Fan, 2003, p. 223).
Vocabulary learning strategy can be seen from at least three different views. First, a vocabulary learning strategy, very broadly speaking, could be what ever the learners do to help the new vocabulary learning process. Whenever a learner needs to study words, he/she uses strategy/strategies to do it. Second, a vocabulary learning strategy could be related to actions that help vocabulary learning to work well. Hence, learners may use some actions which do not make any improvement in learning process. Third, there might be a relation between a vocabulary learning strategy and conscious actions that learners take to study new words. Ideally, in order to have a free chance to choose consciously the suitable strategy for ones self, learners should be informed of 'good', efficient strategies. This fact should be considered that, though, a strategy which is suitable and works well for one student may completely fail with another and that for a particular learning situation one strategy happens to be better than another.
2.2.1. Importance of Vocabulary Learning Strategies
The main advantage obtained from all learning strategies, as well as vocabulary learning strategies, is that learners are able of taking more control of their own learning so that students will fell more responsible for their studies (Nation, 2001; Scharle & Szabó, 2000). Consequently, the strategies develop "learner autonomy, independence, and self-direction" (Oxford & Nyikos, 1989, p.291). When the students be equipped with different kind of vocabulary learning strategies they can decide how exactly they would like to come up with unknown words. Having a good knowledge of the existing strategies and the ability to make use of them in suitable situations might considerably make the learning process of new vocabulary simpler for students for instance, when the student selects which words to study him/her self they can remember the words better than when the words are chosen by someone else (Ranalli, 2003, p. 9). (cited in Gani Hamzah et al., 2009)
In Nation (2001) view learners are able to acquire a large amount of vocabulary with the help of vocabulary learning strategies and that these strategies are truly useful for students of different language levels. As learning strategies are "readily teachable" (Oxford & Nyikos 1989, p. 291), the time that teachers' spend in order to introduce different ways of vocabulary learning and practice to students cannot be considered as wasted. Cameron (2001) believes that children may not be able to make use of vocabulary learning strategies themselves in order to make this happen they need to be trained to use the strategies effectively.
A number of linguists have long recognized the importance of learner independence in vocabulary acquisition. Gairns and Redman (1986) believe that students must show more responsibility for their learning and give larger attention to individual needs. The reason is that when the learners past their elementary level, it would be very difficult for teachers to choose vocabulary being useful to all students; thus time spent on teaching may be wasted. Schmitt (2000) sees the need for solving such problems by helping learners acquire the strategies necessary to learn words on their own. Oxford and Scarcella (1994) support the preparation of systematic vocabulary instruction to let learner master specific strategies to acquire words even outside their classes.
In Nation's view (1990; 2001), the most important way that learners learn vocabulary is when they use strategies independently of their teacher. In his recent publication, Nation suggested strategy training be part of a vocabulary development program.
According to Schmitt and Schmitt (1995), the best teaching plan may be to let students decide themselves which strategy or strategies they prefer by introducing a variety of learning strategies. This echoes learners' need to advance their strategy knowledge.
2.2.2. Types of Vocabulary Learning Strategies
As it is made clear by many vocabulary learning strategy classifications proposed by different researchers, there is a wide range of different vocabulary learning strategies. Most studies in the field of vocabulary learning strategies have focused on investigating a small set of VLSs. For example, some studies point at researching memory strategies or mnemonic techniques and what effect they have on retention (Cohen & Aphek, 1980; Pressley et al., 1982; Brown & Perry, 1991). Some studies put emphasis on exploring the vocabulary strategies used in reading, such as guessing from context (Huckin, Haynes, and Coady, 1993). In the following part we will take a closer look at the most important category of the strategies. The basement of the strategies below is generally organized on Schmitt's (1997) taxonomy, i.e. the names of the broad categories of the strategies come from his classification.
Schmitt's taxonomy of vocabulary learning strategies (cited in Marttinen, 2008)
Schmitt (1997, p. 206-208) based his taxonomy of vocabulary learning strategies on Oxford's (1990) taxonomy of learning strategies. Since Oxford (1990) created the taxonomy for describing learning strategies as a whole in the first step Schmitt (1997) had to revise it in order to act as a useful tool especially when categorizing vocabulary learning strategies.
According to Schmitt's (1997) taxonomy, there are two main groups of strategies: discovery strategies and consolidation strategies. Discovery strategies are those strategies which are used in discovering the meaning of a new word whereas consolidating strategies deal with the consolidation a word once it has been encountered. The former consists of determination strategies and social strategies whereas the latter includes social strategies, memory strategies, cognitive strategies and metacognitive strategies.
However, Schmitt (1990, p.204) notes that "it is very difficult to draw a border line between different strategies and their variations". For example, some strategies, like interacting with native speakers, can be categorized as both social and metecognitive strategy if it is concidered as a part of overall language learning.
When facing an unfamiliar word, learners must find out the meaning of the new word. According to Schmitt (1997, p.208), determination strategies which are a part of discovery strategies, include strategies such as guessing the meaning according to structural knowledge, guessing from L1 cognate, guessing from context or using reference material. Since learners can ask help from someone in discovering the meaning of a new word, social strategies can also function as discovery strategies (Schmitt 1997, p.209).
Consolidating strategies include several different types of strategy. In Schmitt's (1997) taxonomy they include social strategies, since input acts as a key element in acquiring a language, social strategies are very important in language learning. For example, group learning and team working raises active processing and since in such activities instructor does not interrupt the learners much, they have more time to use the language in the classroom (Schmitt 1997, p.211).
Schmitt (1997, p.211-13) mentions that another type of consolidation strategies are memory strategies which were traditionally known as mnemonics. Memory strategies usually make a relation between the word and learners previous knowledge, for example, instead of giving the direct definition or making a kind of relation to some familiar L2 words, pictures of the meaning are shown to learners. Using unrelated words or grouping the words according to some categories such as synonyms or common themes are other examples of memory strategies.
In addition, one can study the spelling or pronunciation of the word for helping it to stick into memory. Furthermore, using word's affixes, roots and word classes can be useful in consolidating word meaning. (Schmitt 1997, p.214)
According to Schmitt (1997, p.215), cognitive and memory strategies of his taxonomy are similar and they concentrate on repetition and mechanical means of studying vocabulary rather than manipulative mental processing. Written and verbal repetitions are the traditional and popular examples of these strategies; writing or repeating a word several times. Word lists, flash cards and note taking as well as using study aids such as language textbooks are also classified as cognitive strategies.
As mentioned before, the strategies which learners use in order to control and evaluate their learning are called metacognitive strategies and this is the same in Schmitt's (1997) taxonomy. Schmitt (1997, p.216) mentions that "effective metacognitive strategies can happen when learners are exposed to L2 as much as possible", for example, by reading books, watching movies and interacting with native speakers. Also using the time effectively and knowing when to actively study a new word are useful metacognitive strategies.
Most of the studies in this area tried to investigate a small set of vocabulary learning strategies. For example some of the researchers (Cohen & Aphek, 1980; Pressely & et al., 1982; Brown & Perry, 1991) centered their studies on memory strategies or mnemonic techniques and its effect on retention. Some other studies emphasized on the vocabulary learning strategies which are used in reading such as guessing from the context (Huckin, Haynes & Coady, 1993). There are a few studies which elaborated on vocabulary learning strategies as a whole and give a broader perspective from them.
The table below summarizes the different classification system of VLS.
1. strategies involving authentic language use
2. strategies used for self-motivation
3. strategies used to create mental linkages
4. memory strategies
5. strategies used to organize words
6. strategies involving creative activities
7. visual/auditory strategies
8. strategies involving physical action
9. strategies used to overcome anxiety
Gu & Johnson (1996)
1. metacognitive regulation
2. guessing strategies
3. dictionary strategies
4. note-taking strategies
5. rehearsal strategies
7. activation strategies
1. discovery strategies 1.1 determination strategies (DET)
1.2 social strategies (SOC)
2. consolidation 2.1 social strategies (SOC)
strategies 2.2 memory strategies (MEM)
2.3 cognitive strategies (COG)
2.4 metacognitive strategies (MET)
1. planning 1.1 choosing words
1.2 choosing the aspect of word knowledge
1.3 choosing strategies
1.4 planning repetition
2. sources 2.1 analyzing the word
2.2 using context
2.3 consulting a reference source in L1oe L2
2.4 using parallels in L1 and L2
3. processes 3.1 noticing
As you have became familiar with Schmitt's taxonomy earlier in this section, now lets take a look at the other classifications mentioned in the table. (Cited in nccuir.lib.nccu.edu.tw/bitstream/140.119/33390/7/55007107.pdf, 2005)
Stoffer (1995) conducted the first investigation of overall vocabulary learning strategies. She fulfilled a vocabulary strategy survey and developed a Vocabulary Learning Strategy Inventory (VOLSI). Using statistical factor analysis which provide a practical basis for category assignment, Stoffer found the 53VOLSI items go under the nine major groups: 1- authentic language use; 2- self-motivation; 3- crating mental linkages; 4- memory strategies; 5- organizing words; 6- creative activities; 7- visual/auditory strategies; 8- physical action; and 9- overcoming anxiety.
Gu and Johnson (1996), developed a vocabulary learning questionnaire based on previous quantitative and qualitative research (Ahmed, 1989; Gu, 1994; Oxford, 1990), that its aim is to gather information on students' beliefs about vocabulary learning and the vocabulary learning strategies which they use (91individual strategies in total). The strategies were grouped under two general subdivisions: Metacognitive regulation and Cognitive strategies which consists of six subgroups, guessing strategies, dictionary strategies, note-taking strategies, memory strategies (rehearsal), memory strategies(encoding), and activation strategies. In this way, in the taxonomy mentioned seven major dimensions exist which each dimension had several categories for it self. For example, guessing strategy was subdivided into two categories: using background knowledge/ wider context and using linguistic cues/ immediate context.
Nation (2001) developed a taxonomy which "tries to separate aspects of vocabulary knowledge, and learning processes." In his classification scheme Nation (2001) differentiates between three general classes of strategies. The first major category is "planning for vocabulary learning" which is concerned about how often learners pay attention and where they focus their attention. Strategies such as choosing words, choosing the aspects of word knowledge, choosing strategies, and planning repetition are included in this category. The second major category refers to "sources of vocabulary knowledge" which is about finding information of unfamiliar words. The strategies in this category include analyzing the word, using context, consulting a reference source in L1 or L2, and using parallels in L1 and L2. The third and last major category is concerned about "learning processes" which includes the ways learners establish their vocabulary knowledge and make it available for use. Noticing, retrieving, and generating are three types of strategies of this category.
2.3. Research background
There are authors such as Nation (2001) and Coxhead (2006) in the vocabulary literature who believe that there is a difference between general, academic, technical, and low frequency vocabulary, mentioning that technical or specialized words have a quite high frequency in a limited range of texts in each academic discipline (Fraser 2005). Scarcella and Zimmerman (1998) make the same difference, and refer to "technical words that are used in specific academic fields" (p. 28). Carlson (1999) and Coxhead and Nation (2001) have written about specialized vocabulary lists for specific purposes.
This is an important issue because Casanave's (1992) study showed that "acquiring the culture of a disciplinary community involves learning that community's specialized language", and Parry (1991, 1993) in his research revealed the challenges of technical, academic vocabulary learning. Fan (1998) found that Chinese EFL learners' have difficulty in "recoding technical vocabulary" and in writing on strategies and long-term recall, Lawson and Hogben (1996) discussed the importance of VLS in a way that is relevant to learning the technical vocabulary of one's academic field:
In the early stages of language learning, when the students do the tasks themselves they are more interested, this is a deliberate processing activity rather than automatic (Hasher & Zacks 1979). The deliberate procedures, or strategies, conducted during this period are likely preserved; these strategies should be seen in student's behavior as they do a vocabulary learning task (p. 104).(Cited in Lessard-Clouston, 2008)
Strategies which learners use in dealing with the technical vocabulary learning in their early stage in the disciplines they have chosen may thus influence both their vocabulary acquisition and their academic socialization. Nation (1993, p.124) stated that "broad vocabulary growth depends on vocabulary strategies that are independent of subject matter knowledge", and there are a number of related VLS studies from the literature of the last decade or so. (Cited in Lessard-Clouston, 2008)
2.3.1. Related researches on the field of VLS
This part tries to give an overview of research focusing on various vocabulary learning strategies.
18.104.22.168. International researches
Sanaoui (1995) in a research among both English and French second language students in Canada came to this conclusion that while a learner's proficiency level and type of instruction did not affect his or her results on an individualized vocabulary assessment task, the individual approach to vocabulary study, reflected in the structured use of VLS, did contribute significantly to lexical learning. Sanaoui used a detailed questionnaire to find out which strategies participants' use for learning vocabulary, that distinguished two distinct approaches to vocabulary acquisition, structured and unstructured, which are different in five key aspects: a) learners' opportunities for learning vocabulary (i.e., independent study vs. reliance on their language course); b) their range of self-initiated vocabulary learning (i.e., extensive vs. restricted); c) their records of the lexical items they were learning (i.e., extensive/systematic vs. minimal/ad hoc); d) how much learners reviewed such words/records (i.e., extensively vs. little or not at all); and e) whether they practiced such lexical items (i.e., by creating opportunities in and out of class vs. relying on class opportunities alone) (Sanaoui, 1995). (Cited in, Ruutmets, 2005)
In a research with 14 ESL students preparing for academic study in Canada, however, Lessard-Clouston (1996) also followed Sanaoui's model and used a questionnaire and an individualized vocabulary test. Despite replicating the most important aspects of Sanaoui's (1995) research, his results showed that membership in a group, based on a participant's VLS, did not predict language proficiency, nor performance on the individualized vocabulary knowledge test. Lessard-Clouston (1996) thus concluded that such "findings raise questions about the usefulness of categorizing students in groups according to structured, semi-structured, or unstructured approaches to lexical learning" (p. 114).(cited in, Lessard-Clouston, 2008)
A study conducted by Gu and Johnson (1996) among 850 non-English major Chinese students in China, a questionnaire and multiple regression analysis revealed two VLS, self-initiation and selective attention, as positive predictors of their participants' proficiency, measured by their college English test scores. They also found that the strategies of contextual guessing, skillful dictionary use, paying attention to word formation, contextual encoding, and using newly learnt words had a positive correlation with participants' test scores. Using cluster analysis Gu and Johnson found five key approaches to vocabulary learning (encoders, readers, active strategy users, non-encoders, and passive strategy users), and came to this point that strategy combinations, rather than individual VLS, may have a positive effect on their participants' learning.(cited in, Xhaferi, 2008)
Schmitt (1997) prepared a VLS taxonomy using Oxford's (1990) work, distinguishing two broad types: discovery strategies (for initially learning a word's meaning) and consolidation strategies (for remembering and using a word once it has been encountered), there may be some VLS in common for both. Schmitt asked 600 Japanese EFL learners using a survey to say how often they use different VLS, what they fell about the helpfulness of those strategies, and to mention the most helpful ones. Six strategies were common among the VLS rated most used and most helpful, which includes: using a bilingual dictionary, written repetition, verbal repetition, saying a new word aloud, studying a word's spelling, and taking notes in class. Evaluating the results of the survey of strategies reported by groups of middle school, high school, university and adult EFL learners, Schmitt (1997) also noted that "for some VLS the patterns of strategy use appeared to change over time "(p. 224).(cited in, Xhaferi, 2008)
Kojic-Sabo and Lightbown (1999) have done their research using a questionnaire adapted from Sanaoui's work, a Yes/No test of academic vocabulary, and a cloze test for collecting data on the vocabulary learning approaches of 47 EFL and 43 ESL students in Yugoslavia and Canada. Their main findings strongly supported Sanaoui's conclusions, which is more frequent and elaborate strategy use "is linked to success in language learning, whereas lack of effort on the learners' part relates to poor achievement" (p. 190). In addition, time and learner independence were found to be the two measures that are closely related "to success in vocabulary learning and higher overall English proficiency" (p. 176). (cited in, Ruutmets, 2005 )
Fan (2003) conducted a large scale research, studying Chinese EFL learners in Hong Kong, evaluating the vocabulary tests and strategy questionnaires completed by more than 1,000 university students. Fan discovered that the most proficient participants of her study used several different strategies (notably using more sources, dictionaries, guessing, and known word strategies) significantly more often than the less proficient ones (p. 233), and she echoed Sanaoui's (1995) view on the importance of review and consolidation in vocabulary learning (p. 234). Fan also noticed that strategy use are very complex and various noticeable differences existed between frequency of use and the reported, perceived usefulness of particular VLS of participants' of her study. Fan (2003) thus concluded by emphasizing on the importance of helping EFL students understand the significance of VLS and encouraging them to develop effective strategies of their own.(cited in, Fan, 2003)
In contrast with the large-scale studies mentioned earlier, which emphasize learners' reported strategy use, Gu (2003) conducted a detailed case studies on the VLS of two successful Chinese EFL students (who were not English majors) using reading tasks, think-aloud protocols, and interviews to document their observed use of VLS. Building on their preferred learning styles (auditory and visual), Gu's participants were highly motivated and employed a range of cognitive and metacognitive strategies and approaches in their EFL vocabulary learning. Gu (2003) concluded that the combination of these strategies and approaches created a 'vocabulary-learning art' in which each participant exhibited "...the flexible and skillful analysis, choice, deployment, execution, and orchestration of all strategies at their disposal in accordance with their own preferred style of learning" (p. 99). Gu's (2003) study also revealed the value of interviews and case studies for VLS research. (cited in, Lessard-Clouston, 2008)
There are some other notable researches. Peacock and Ho (2003) surveyed 1,006 Hong Kong EAP students in eight different disciplines and found that students in different fields use different language learning strategies, some of which correlated more highly with their participants' English proficiency. Cognitive and metacognetive were the most frequent strategies used by students, and follow up interviews with 48 participants revealed that students outside of the humanities tended to use fewer strategies and viewed studying English to be of less importance than their disciplines.(cited in, Peacock & Ho, 2003)
Parks and Reymond (2004) have done a research with 28 Chinese NNES students studying MBA in Canada, they reported that the strategies their participants use varied significantly and changed over time, especially when later in the program for their study NNES students interacted with NES students in regular classes. Parks and Raymond thus concluded: "In contrast to the rather simplistic notion evoked in certain portrayals of the good language learner, strategy use as reported herein emerges as a complex, socially situated phenomenon, bound up with issues related to personal identityâ€¦" (p. 374). (cited in Park & Reymond, 2004 )
In a recent, short term study Atay and Ozbulgan (2007) examined the VLS of 50 military ESP learners in Turkey, which its participants took part in a three week period study in two separated classes that each class was held for six hours a day. For comparing the two English "Air Traffic Terminology" classes Atay and Ozbulgan used a multiple-choice vocabulary test and a strategies questionnaire (p. 42). In their study they had two groups: a control group with no special training and an experimental group which was introduced to VLS and spent one of the six hours in class each day on focused "memory strategy instruction" (p. 44). On the vocabulary knowledge post-test, learners in the experimental group gained significant higher test scores than the control group (p. 45). The results of the strategies questionnaire among learners in the experimental group also indicated a major "increase in the percentage of use and variety of strategies in the post-test" (p. 46). (Cited in Atay & Ozbulgan, 2007 )
22.214.171.124. National researches
Eslami Rakhsh and Ranjbary (2003) investigated the metacognitive strategy training effects on the lexical knowledge development of 53 male and female Iranian students taking part in an intensive course of English in Tehran Institute of Technology aged 19 to 25. The results showed no significant difference in the vocabulary knowledge between two groups. However, the result of the post-test showed something different. At the end of the experience the experimental group showed progress in terms of lexical knowledge comparing to control group. Thus, the findings of this study indicate that explicit metacognitive strategies instruction has a positive impact on the lexical knowledge development of EFL students.(cited in, Kafipour et al., 2011 )
Marefat and Ahmadi (2003) studied on 60 Iranian female English language learner between the age of 15 and 17,in this study they wanted to examine the effect of teaching direct learning strategies (memory, cognitive, and compensation) and their subcategories on the vocabulary short term and long term retention. In fact, they are not concern about vocabulary learning strategies in this study; rather they want to examine the impact of learning strategies on vocabulary retention. As the result of the questionnaire showed, memory and cognitive strategies were used more than other strategies; moreover, learners' strategy use in short-term retention vocabulary was more effective than in long-term retention.
The results also revealed the superiority of memory strategy use both in short and long term retention.(cited in, Kafipour et al., 2011 )
Alavi (2006) in a research with 231 TEFL and non-TEFL undergraduate university students tried to investigate the frequency of use of cognitive and metacognitive vocabulary learning strategies. In order to do this three questionnaires were used, Oxford's (1990) classification of language learning strategies, Wenden's (1987) classification of strategies, and Gu and Johnson's (1996) vocabulary learning questionnaire (VLQ). The results indicated that Iranian university students prefer cognitive strategies and they use it more frequently in their vocabulary learning process. The results also revealed that there is a significant relation between students major and their choice of strategies, their major significantly affects their choice. (cited in Alavi, 2006)
Akbary's and Tahririan's (2009) study can be regarded as one of the recent studies in vocabulary learning strategy area. They investigated vocabulary learning strategies use for specialized and non-specialized learning vocabulary among ESP students in different field of studies. 103medical and paramedical undergraduate Isfahan University of Medical Sciences students from 8 majors participated in this study all of which were passing their ESP course. For data elicitation three different methods were used; observation, interview and questionnaire. The finding of the questionnaire showed that the most frequent strategy was using bilingual dictionaries and the most commonly used learning strategy was oral and written repetition.(cited in, Akbary & Tahririan, 2009)
Gani Hamzah, Kafipour and Abdullah (2009) conducted a study in order to evaluate undergraduate EFL learners vocabulary learning strategies and its relation to the learners vocabulary size. 125 Iranian TEFL undergraduate students took part in this study. Two instruments were used to collect the data; Nation's standardized vocabulary size test and Schmitt's vocabulary learning strategy questionnaire adopted from Bennet (2006). The collected data were analyzed by descriptive statistics and multiple regression. The results indicate that Iranian undergraduate EFL learners are medium strategy users and determination strategy was the most frequently used and social strategy was the least used frequently strategies. Also the results showed a significant contribution between VLSs and learners vocabulary size. (cited in Gani Hamzah et al., 2009)
In a research done by Kafipour and Hosseini Naveh (2011) on investigating the vocabulary learning strategies use by EFL undergraduate students of Kerman province and its contribution to reading comprehension 164 EFL undergraduate students from Kerman province were chosen. For data collection Schmitt's vocabulary learning strategy questionnaire (VLSQ) adopted from Bennett (2006) and TOEFL reading comprehension test were used. For analyzing the collected data descriptive statistics and stepwise multiple regression were used. The results of descriptive statistics indicate that EFL undergraduate students in Kerman Province are medium strategy users and they use metacognitive strategies more frequently than other four strategies and social strategies stands as the least frequently strategy used. The results related to stepwise multiple regressions revealed only contribution of social strategy (one out of 5 categories of vocabulary learning strategies) to reading comprehension. (Cited in Kafipour & Hosseini Naveh, 2011)
In a study conducted by Khatib, Hassanzadeh and Rezaei (2011) under the title of "vocabulary learning strategies of Iranian upper-intermediate EFL learners" they wanted to examine the preferred vocabulary learning strategies of Iranian upper-intermediate EFL learners. In this study 146 undergraduate EFL students participated from Vali-e-Asr university of Rafsanjan. Two instrument were used in this study: a TOEFL test for identifying participants language proficiency level and a VOLSI questionnaire (Vocabulary Learning Strategies Inventory) to find out their preferred vocabulary learning strategies. The stepwise multiple regression analysis showed that three strategies (self-motivation, word organization, and authentic language use) out of nine were significant predictors of L2 proficiency. (Cited in Khatib et al., 2011)