Teaching English Vocabulary with Greek or Latin Roots to Iranian EFL Students by PLS Sequential Structures

PLS is a newly developed language teaching method which predominantly applies imaginative and random usage of pictures. The present paper explains and reports the application of a PLS technique in teaching English vocabulary with Greek or Latin roots to Iranian EFL learners. A pretest-posttest control-group design was used to investigate the effects of this sequential structures technique. Participants were intermediate level EFL students in two branches of the same language institute in Tehran (N = 94, p ≤ 0.05). The subjects were randomly assigned into two groups of treatment and control. The experiment lasted for seven one-hour lessons held in successive sessions in three weeks during which 35 Greek and Latin roots were taught with at least three English word examples. For the research instrument, the students were administered a 35-item multiple-choice vocabulary exam for the pre and post tests prior to and immediately after the teaching phase. Consequently, an independent sample T-test was used to examine the outcome of the experiment. At p = .009, the statistical test revealed a significant difference in the gain scores between the two groups. Also, the mean vocabulary gain score of 7.23 for the treatment group as opposed to the mean of 5.35 for the control group illustrated the relative more L2 vocabulary intake for the treatment group.

can be of great importance, especially because of the power it provides the L2 learners by which they can guess the meaning of several words they see or hear for the first time. Nevertheless, to the best knowledge of the author, there has not been an exclusive study as to how to teach vocabulary with Greek or Latin roots in EFL/ESL contexts. There are, however, many interesting courses and lesson plans on the Internet such as "Engaging activities for Greek & Latin Roots", and "Complete List of Root Words". There are also several substantial dictionaries or thesauri on this topic, such as Danner (2014).
The present study reports an experiment in which L2 learners are taught Greek and Latin roots with several related examples. It will be illustrated that by implementing the PLS sequential structures, language learners will be able to associate various range of meanings to different words, and by doing so store them in their L2 vocabulary repertoire more effectively.

Teaching English Vocabulary in Retrospect
There is a rich and substantial literature on the English vocabulary teaching/ learning trends among various methods and approaches in the field such as (Brown, 2000;Celce-Murcia, 2001;Larsen-Freeman & Anderson, 2011;Nunan, 2003;Richards & Renandya, 2002;Richards & Rodgers, 1990;Smith, 1996;Zimmerman, 1997). For instance, students generally make use of bilingual word lists in the Grammar Translation Method. In GTM, the target language is viewed as a tool for the mind to practice with. Hence, the etymologies of the words are typically emphasized and studied. In the Direct Method, on the other hand, oral skills have been given priority over the written ones. So, pictures and teacher's gestures are used to teach concrete words, whereas abstract words are taught based on the topics in hand. In the Audio-Lingual Method, words are chosen based on their being simple or familiar to the learners. Selection of new words in ALM is somehow limited due to the need of fitting them in appropriate drills. Furthermore, teachers in both DM and ALM are not allowed to translate words. Then, Communicative Language Teaching emphasizes communication and the ability to use the language functionally. According to Zimmerman (1997), learning vocabulary is a pivotal activity for every L2 learner. Likewise, Laufer (1998) states that vocabulary is an essential constituent of fluency in speech. Also, according to Nation (1990), vocabulary is probably the most essential element in learning a language. Nation suggests word-frequency counts as a good measure to choose the vocabulary to teach because they can help teachers and course designers develop a criterion as to which words are more useful and which ones are not frequently used. Finally, according to Schmitt (2008), learning vocabulary is a fundamental part of mastering a second language, and that L2 learners and teachers, as well as decision makers must take this fact into consideration.
From another perspective, Smith (1996) postulates that people have "working" and -perhaps-"non-working" vocabulary. This notion can also be referred to as "passive" and "active" vocabulary. By "passive vocabulary" we mean those words that one can easily understand and comprehend when words accompanied by a list of vocabulary and grammatical content list (Richards & Rodgers, 1990).
Then as to the quality of the vocabulary, we can think of different aspects such as the frequency, degree of difficulty, degree of formality, coverage, usage, etymology, etc. of the words, each of which could be a good subject for a research (Hashim & Hassan, 2006;Smith, 1996). Moreover, we can consider types of lexical relations in a specific language like synonymy, antonymy, hyponymy, homophony, homonymy, and polysemy (Palmer, 1981;Yule, 2017). Yet, another conceivable classification of words that exist in any language can be the dichotomy of concrete vs. abstract vocabulary. To sum up, it is wise to assume that the knowledge of the above-mentioned associations within different L1 and L2 words intralingually, as well as the relations among different components of the mother tongue and the target language interlingually, such as the existence of cognates, or the language of instruction would be of great importance.

Which Method/Technique to Choose?
There have been various studies on strategies, techniques, or approaches used in teaching/learning English vocabulary such as usage of keywords: correlating the L2 word with an L1 keyword which is acoustically or orthographically alike, and by doing so, linking the L1 keyword with the L1 translation of the L2 word (Brown & Perry, 1991), semantic and thematic clustering (Tinkham, 1997), role of pedagogical tasks and form-focused instruction (De la Fuente, 2006), usage of word pairs (Webb, 2009), reading thematically related texts (Paribakht & Wesche, 1999), incidental vocabulary learning (Wode, 1999), intentional vocabulary learning (Brown, 2010), rote rehearsal vs. context/keyword methods (Rodriguez & Sadoski, 2000), input-based and production-based instruction (Shintani, 2011), use of categorical lists (Hoshino, 2010), explicit instruction of vocabulary (Mizumoto & Takeuchi, 2009), code-mixing: the use of L1 word in an L2 utterance (Celik, 2003), semantic transfer (Jiang, 2004), focus on Knowledge of affixes and morphological awareness (Noprianto & Purnawarman, 2019;Sarfraz, Tariq, & Abbas, 2018), spontaneous vocabulary reactivation (Meara, 2005), rote memorization, that is to memorize the L1 translation of a new L2 term; as opposed to semantic mapping that is to show the L1 words conceptually linked to the L2 word in a chart (Sagarra & Alba, 2006); and finally, using multiple strategies simultaneously, (Nosidlak, 2013). Additionally, many studies have shown that new words in EFL/ESL setting can be stored and retrieved more efficiently by stronger association load (Chen & Chung, 2008;Hulstijin, 2001;Keating, 2008;Mizumoto & Takeuchi, 2009;Schmitt, 2008 to produce as many structures as possible, and to try to prolong the whole sentence configuration. This technique can be applied both orally and in written forms. Table 1 illustrates an example in which a random picture is used to introduce five Greek/Latin roots and their corresponding English vocabulary.
Please also see Appendix A for more examples. As can be seen in the following lines, each English word is introduced in stages. There are virtually no limits to the kind of structures and their quantity, as there are no limits to our imagination. In some cases, the certain word might be introduced in the first structure, and then reinforced by the structures which follow.

Sentence sequence 1:
1-Some people lose their home keys frequently.
2-Psychology allows us to study their behavior as to why they lose their keys. 3-A few scholars believe that psychology is a sub-branch of anthropology.

Sentence sequence 2:
1-Lab research is the key to find answers to our big questions.
2-Medicine particularly depends on lab research a lot.
3-A good example is the developing and production of various antibodies.

Sentence sequence 3:
1-My friend lives in a very big house.
2-This is the key to my friend's house.
3-My friend's largest room is his library.
4-He keeps thousands of books there.

Sentence sequence 4:
1-This key is made of metal.
2-It's been plated by chromium for beauty and more endurance.

Sentence sequence 5:
1-Punctuality is one of the keys to success nowadays.
2-To be on time, we must rely on some devices.

3-For example, a chronometer measures the passage of time.
Totally 35 Latin or Greek roots were used in the present study. For each root, at least three corresponding English vocabulary were taught. Appendix B lists these roots and the related English vocabulary.

Research Goal
The aim of the data collected in this pre-test and post-test control-group study was to examine whether or not teaching Greek and Latin roots to EFL students via Pictologics method is practical and effective, as compared to using conventional teaching methods.

Subjects
Totally, 94 EFL students in two branches of the same language institute in Tehran participated in the present study. They were randomly assigned into two groups: treatment (46 students), and control (48 students). Each group comprised of students who studied in two intermediate level classes in the same branch. The majority of these L2 learners were either senior high school or college freshmen students (age 15-20). As for their English language proficiency level, they either had already passed the elementary and pre-intermediate levels in the same language institute, or else had passed the entry oral and written placement tests. There were 20-26 students in each classroom.

Procedure
The present study was conducted pertinent to the restricted syllabi of the language institute, and as complementary lessons to enrich students' English vocabulary. Two teachers of approximately the same experience taught the two groups. The treatment group received the lessons based on the PLS sequential structures technique; whereas, the control group received the lessons in a conventional way in which the teacher introduced and used each root and the related English words in just a single sentence or unrelated sentences. Both groups were allowed to use their mother tongue if needed. The total time allocation to the teaching process was seven one-hour lessons held in consecutive sessions in three weeks.

Instrument
As mentioned before, 35 Greek and Latin roots were taught each of which was introduced at least with three examples. Accordingly, the author made a 35-item multiple-choice vocabulary test for the pre and post exams (Appendix C). As for the type of the questions in the test, definition style items were used.
The rationale for adopting such format was that this type of questions has been used in many websites which teach English vocabulary online. It is also the way most dictionaries use to give the denotative meanings of each word. Likewise, Susanti, Tokunaga, Nishikawa and Obari (2017) introduce several language practitioners worldwide who have used this type of vocabulary tests, sometimes referred to as the "gloss". Additionally, in order to minimize the memory effect, the test items and the choices were randomized in the two tests.

Research Question and Hypotheses
Based on the objective of the current experiment, the following research question and null hypothesis and directional hypothesis where formed.
1-Is there any significant difference between the gain scores achieved by the Iranian EFL students who learnt Greek and Latin roots via PLS sequential structures, and those who learnt them via the conventional method?
H 0 -There is no significant difference between the gain scores achieved by the Iranian EFL students who learnt Greek and Latin roots via PLS sequential structures, and those who learnt them via the conventional method.

Data Analysis
In the present study, the gain scores were calculated by subtracting the pre-test vocabulary grades from the post ones for each individual student. Furthermore, the normality of the gain scores for each group had been checked prior to the group comparison. Subsequently, as illustrated in Tables 2 and 3  normality for both groups. Then, as the parametric statistics used in the present study was an independent samples t-test, then three assumptions of independence of observations, normality of the scores distribution, and homogeneity of the variances needed to be met. As mentioned before, the treatment and control students were randomly assigned into two different groups. In addition, the two teachers were not informed about the other group's lesson plans. Therefore, the independence of observations has been fully observed in this design.
Moreover, concerning the normality of the distribution of the gain scores for both groups together, we should look at the descriptive statistics results as shown in Table 4.   Table 4 shows that the mean of 6.27 is very close to the median of 7.00 in both groups. We can also look at the skewness value in which we can see that the skewness of -.248 is small as compared to the standard error of .249, so the skewness is not a problem here. Also, the kurtosis value of .113 is smaller than the standard error of .493 showing that kurtosis is not a problem here, either.
Additionally, the Shapiro-Wilk test of normality gives us a significant value of .127 which is larger than the cut-off p value of .05 suggesting that the distribution of gain scores is normal.
Then in order to determine if the assumption of the homogeneity of the variances has been met, we must inspect the results of the independent samples t-test as shown in Table 5. should do the calculations on our own using the information provided in the output. The procedure for calculating and interpreting eta squared is by using the following formula as described by Pallant (2005): Eta squared = 2.675 2 2.675 2 + (46 + 48 − 2) = .072

Results
As illustrated in Table 5, in the current test we have t (92) = 2.675, p = .009 As the p = .009 is less than the required cut-off value of .05, the null hypothesis is rejected and we can conclude that there is a statistically significant difference in the Greek and Latin roots gain score between the control and treatment groups. Furthermore, as for the direction of the difference, we saw in Table 2 that the mean vocabulary gain score of 7.23 for the treatment group is larger than the mean vocabulary gain score of 5.35 for the control group. Therefore, we can conclude that those students who were taught with the PLS sequential structures have higher vocabulary gain score than those who were under the conventional method.
Additionally, the effect size has been calculated at .072. According to Cohen (1988), the guidelines for interpreting this value are: .01=small effect, .06=moderate effect, .14=large effect. Thus, we would claim that the effect size of .072 for this test is rather a moderate effect. Then, if we multiply this value by 100, we can have the percentage, suggesting that approximately 7 percent of the variance in vocabulary gain score is explained by the two different teaching methods.

Discussion
The present study showed that involving L2 learners in using imaginative association of English words with Greek or Latin roots in a series of structures can be more effective than a conventional method in enhancing students' English vocabulary intake. These findings are in tandem with the study of Sarfraz,

Tariq and Abbas (2018) in which morphological awareness was proven effective in improving students'
English in a Pakistani university. Moreover, regarding the way the PLS sequential structures is applied, we might rightfully assume that this effect is somewhat similar to what is reported in studies like (Chen & Chung, 2008;Keating, 2008;Mizumoto & Takeuchi, 2009;Schmitt, 2008) in that stronger association load can improve the storage and retrieval of L2 vocabulary in EFL/ESL contexts. These meaningful associations/connections might be reminiscent of 'schematic knowledge', and in this sense, the findings of the present study support that of Shirban Sasi (2019)'s research in which Malaysian elementary school students were taught to use imaginative questions in order to add (or reform) the new chunks of information into their earlier schematic word storage. Furthermore, the current study supports the results of the experiment by Tinkham (1997) in that semantic clustering makes learning the vocabulary more difficult, while thematic clustering serves as a facilitator of new language vocabulary learning. Likewise, the findings of the current study are in tandem with Hennings (2000)'s assertion in that L2 learners learn clusters of words rather than one word when they analyze, sort and search for related words instead of memorizing their definitions. The findings of the current study also agree with Shirban Sasi (2020)'s report in which Taiwanese university students' passive words were activated and reactivated by instigating their imagination by using random picture combinations.
From another perspective, that a teacher or student can imaginatively associate series of structures while intentionally using certain words (or phrases) can be viewed under the topic of critical thinking.
More precisely, in applying PLS sequential structures, at least two traits of recognition of different causes of a problem (various plausible associations), and selection among alternatives with the use of a methodic reasoning (the seemingly unrelated structures to be thought of and related to one another) are frequently practiced. These two are among the critical thinking skills supported by many researchers such as (Angeli & Valanides, 2009;Glassner & Schwarz, 2007;Nakagawa, 2011;Popil, 2011).

Conclusion
The findings of the current study illustrated that students in the treatment group under PLS sequential structures technique learnt the English words with Greek or Latin roots more effectively relative to the control group. The author presumes that learning a foreign or second language can be an enjoyable process if the students believe they are capable of producing seemingly unrelated thoughts and pieces of language. The challenge itself is an effective instigator. Thus, the author suggests that applying this PLS technique, alone or in conjunction with the already existing conventional techniques and methods be considered by L2 teachers and students.

Recommendations for Further Research
In light of the data presented in the current article, the author wishes to suggest the following topics for 1-A jockey fell down during the horse race last summer.

2-He broke his leg.
3-His friends came to see him in order to sympathize with him.

Sentence sequence 2:
1-Any idea about the Trojan Horse mentioned in Iliad?
2-Iliad was created by Homer.
3-Homer was a great Greek poet.
4-Greece was also the homeland of ancient philosophy.
2-Yet, this has never prevented him from horse riding.

Sentence sequence 4:
1-My aunt is a postgraduate student.

2-She is majoring in animal bio-technology.
3-She is currently conduction a research on mammals.

Sentence sequence 5:
1-Vets and doctors use some similar medical devices.
2-Both normally carry a stethoscope.

Sentence sequence 6:
1-Many people bet on horses in horse races.

2-To bet is a kind of gambling.
3-Gambling is not a good way to earn your living.
4-You should expect wicked consequences if you gamble. 1-The earth is full of beauty.
2-Cosmonauts can see the earth from outer space. They can surely appreciate it there better.

Sentence sequence 2:
1-This island is located in the tropical zone.
2-There are variety of different kinds of weather in the world.
3-One can refer to a good encyclopedia to know more about various climates.

Sentence sequence 3:
1-Once upon a time, a cruel king ruled on this island.
2-He was so selfish that he always dictated everything to his people.

Sentence sequence 4:
1-A lot of trees grow on this island.

2-Wood comes from the trees.
3-Wood is not a conductor of electricity.

Sentence sequence 5:
1-An island is a piece of land which is surrounded by water.
2-I learnt this in my geography class.

Sentence sequence 6:
1-My grandfather liked listening to the music of the waves.
2-He had some nice records of this kind of music.

2-You can find various kinds of animals in jungles.
3-They are all heterogeneous as far as size is concerned.

Sentence sequence 2:
1-Last week my friend and I went on a picnic in this forest.
2-We drove my cousin's car which had hydraulic controls.

Sentence sequence 3:
1-Owls are usually found in old ruins or cemeteries.
2-Old places are where archaeology is truly practiced in the field.

Sentence sequence 4:
1-We really have to protect our jungles.
2-The raw materials of many things that we manufacture come from jungles.

Sentence sequence 5:
1-In stories, crows are notorious of being kleptomaniac animals.
2-Some people also suffer from kleptomania.
2-Animals also show maternal care towards their offsprings. 1-These people live away from modern societies.

Sentence sequence 2:
1-These two live in a tribe in a remote place in the Far East.
2-For them, even fulfilling the basic needs seem to be sophisticated issues.

Sentence sequence 3:
1-Tibet is called "The Roof of the World".
2-Do remember to take enough equipment with you if you are planning to go there.

Sentence sequence 4:
1-People who live in remote places have many obstacles to overcome.
2-They do not normally have access to the modern technology.

Sentence sequence 5:
1-I know which tribe these people belong two.
2-I have watched a television documentary film about them.
2-In some other countries, people worship only one God.
3-Worshipping just one God means being monotheistic.