Supplementary Material

TABLE 1. Topics with increasing interests

Type Key words

1997-2007 2008-2018

LL BICRaw Num

Norm.Num

Raw Num

Norm.Num

Increase with positive evidence (BIC> 2), strong evidence (BIC > 6.86) or very strong evidence (BIC >22.22) au mixed-method 2 1 86 17.6 34.76 24.10

ad semi structured interview 0 0 43 8.8 24.11 13.45

au multilingualism 0 0 40 8.2 22.42 11.77

au eye-tracking 2 1 59 12 21.11 10.45

au blog 3 1.5 58 11.8 17.04 6.39

au English as a foreign language 60 30.6 318 64.9 16.53 5.88

au teacher cognition 0 0 29 5.9 16.26 5.61

au executive control 0 0 28 5.7 15.70 5.05

au wiki 0 0 28 5.7 15.70 5.05

au adaptation 1 0.5 39 8 15.33 4.68

au bilingual advantage 0 0 27 5.5 15.14 4.48

au ideal L2 self 0 0 26 5.3 14.58 3.92

au affordance 6 3.1 71 14.5 14.56 3.91

ad artificial language 0 0 24 4.9 13.45 2.80

ad efficacy 14 7.2 107 21.8 12.73 2.08

Increase with evidence (LL > 3.84)au social networking 0 0 22 4.5 12.33 1.68

ad L2 self 1 0.5 33 6.7 12.29 1.64

au usage-based 1 0.5 33 6.7 12.29 1.64

au web 2.0 0 0 21 4.3 11.77 1.12

ad dynamic system 1 0.5 30 6.1 10.80 0.15

au telecollaboration 1 0.5 30 6.1 10.80 0.15

au English as a lingua franca 0 0 19 3.9 10.65 --

ad collaborative writing 1 0.5 29 5.9 10.31 --

au emotion 13 6.6 94 19.2 10.17 --

ad Common European framework 0 0 18 3.7 10.09 --

au languaging 0 0 18 3.7 10.09 --

ad verbal working memory 0 0 18 3.7 10.09 --

au priming 16 8.2 106 21.6 9.70 --

au interface 0 0 17 3.5 9.53 --

au cognitive control 1 0.5 27 5.5 9.33 --

ad lingua franca 2 1 34 6.9 9.25 --

au self-paced reading 3 1.5 39 8 8.70 --

au computer assisted language learning (CALL) 12 6.1 84 17.1 8.56 --

au content and language integrated learning 0 0 15 3.1 8.41 --

au linguistic complexity 0 0 15 3.1 8.41 --

au masked priming 0 0 15 3.1 8.41 --

au morphological processing 0 0 15 3.1 8.41 --

au structural priming 0 0 15 3.1 8.41 --

au eye movement 2 1 32 6.5 8.36 --

ad working memory 20 10.2 118 24.1 8.29 --

au modality 7 3.6 59 12 8.16 --

au lexical diversity 2 1 31 6.3 7.92 --

au morphological awareness 3 1.5 37 7.6 7.88 --

au Chinese 108 55.2 447 91.3 7.86 --

au blended learning 0 0 14 2.9 7.85 --

au facebook 0 0 14 2.9 7.85 --

au google 0 0 14 2.9 7.85 --

au language teacher cognition 0 0 14 2.9 7.85 --

au multimodality 0 0 14 2.9 7.85 --

au teacher identity 0 0 14 2.9 7.85 --

au task design 3 1.5 36 7.3 7.48 --

ad self-system 1 0.5 23 4.7 7.40 --

au collaborative task 0 0 13 2.7 7.29 --

ad stroop task 0 0 13 2.7 7.29 --

au perception 85 43.4 360 73.5 7.27 --

au collocation 10 5.1 70 14.3 7.13 --

au L2 motivation 3 1.5 35 7.1 7.08 --

au elicited imitation 1 0.5 22 4.5 6.92 --

au dictogloss 0 0 12 2.4 6.73 --

au grammatical aspect 0 0 12 2.4 6.73 --

au mobile assisted language learning 0 0 12 2.4 6.73 --

au n400 0 0 12 2.4 6.73 --

au syntax discourse interface 0 0 12 2.4 6.73 --

au task repetition 0 0 12 2.4 6.73 --

ad memory capacity 3 1.5 34 6.9 6.69 --

au self-efficacy 7 3.6 54 11 6.52 --

au sign language 4 2 39 8 6.52 --

au cognitive load 1 0.5 21 4.3 6.45 --

au learner corpus/corpora 2 1 27 5.5 6.22 --

au child language 0 0 11 2.2 6.17 --

ad genre based 0 0 11 2.2 6.17 --

au inhibitory control 0 0 11 2.2 6.17 --

au plurilingualism 0 0 11 2.2 6.17 --

au social network 0 0 11 2.2 6.17 --

ad Spanish heritage speaker 0 0 11 2.2 6.17 --

ad task-based 22 11.2 117 23.9 6.15 --

au age effect 1 0.5 20 4.1 5.99 --

ad peer feedback 1 0.5 20 4.1 5.99 --

au corrective feedback 20 10.2 108 22 5.95 --

ad natural language 3 1.5 32 6.5 5.92 --

au cross language activation 0 0 10 2 5.61 --

au second language teacher education 0 0 10 2 5.61 --

au second life 0 0 10 2 5.61 --

au translanguaging 0 0 10 2 5.61 --

au inhibition 3 1.5 31 6.3 5.54 --

au data driven learning 1 0.5 19 3.9 5.53 --

au task complexity 2 1 25 5.1 5.39 --

ad working memory capacity 3 1.5 30 6.1 5.16 --

au synchronous computer mediated communication 4 2 35 7.1 5.10 --

au dynamic systems theory 1 0.5 18 3.7 5.07 --

au automatic speech recognition 0 0 9 1.8 5.05 --

ad declarative/procedural memory 0 0 9 1.8 5.05 --

au involvement load hypothesis 0 0 9 1.8 5.05 --

au lexical complexity 0 0 9 1.8 5.05 --

au online language learning 0 0 9 1.8 5.05 --

au statistical learning 0 0 9 1.8 5.05 --

au task switching 0 0 9 1.8 5.05 --

au visual word recognition 0 0 9 1.8 5.05 --

au language dominance 2 1 24 4.9 4.99 --

au task based language teaching 2 1 24 4.9 4.99 --

au study abroad 25 12.8 123 25.1 4.96 --

au Mandarin 21 10.7 107 21.8 4.89 --

au motion event 1 0.5 17 3.5 4.62 --

au pedagogical content knowledge 1 0.5 17 3.5 4.62 --

au cognition hypothesis 0 0 8 1.6 4.48 --

au formulaic language 0 0 8 1.6 4.48 --

au learner agency 0 0 8 1.6 4.48 --

au learner attitudes 0 0 8 1.6 4.48 --

ad mixed effects model 0 0 8 1.6 4.48 --

au ought to L2 self 0 0 8 1.6 4.48 --

ad Simon task 0 0 8 1.6 4.48 --

au technological pedagogical content knowledge 0 0 8 1.6 4.48 --

au verbal fluency 0 0 8 1.6 4.48 --

au L2 pragmatics 0 0 8 1.2 4.48 --

au language teacher education 5 2.6 38 7.8 4.48 --

au late bilinguals 3 1.5 28 5.7 4.44 --

au explicit instruction 11 5.6 64 13.1 4.34 --

au comprehensibility 6 3.1 42 8.6 4.28 --

au technology 43 22 186 38 4.22 --

au extensive reading 1 0.5 16 3.3 4.18 --

au metalanguage 1 0.5 16 3.3 4.18 --

ad morphologically complex word 1 0.5 16 3.3 4.18 --

au stimulated recall 10 5.1 59 12 4.15 --

au error correction 4 2 32 6.5 4.09 --

ad learning strategies 36 18.4 73 14.9 4.06 --

au computer mediated communication 14 7.2 75 15.3 4.03 --

au attentional control 0 0 7 1.4 3.92 --

au cross language priming 0 0 7 1.4 3.92 --

ad differential object marking 0 0 7 1.4 3.92 --

au feature reassembly 0 0 7 1.4 3.92 --

au flipped classroom 0 0 7 1.4 3.92 --

au infancy 0 0 7 1.4 3.92 --

ad semantic transparency 0 0 7 1.4 3.92 --

au shallow structure hypothesis 0 0 7 1.4 3.92 --

au task based language learning 0 0 7 1.4 3.92 --

Notes: 1. au = author-supplied-keyword; ad = keyword-from-abstracts; LL = Log-likelihood; BIC = Bayes Factor (Wilson, 2012).2. LL and BIC were calculated using raw frequencies (Rayson & Garside, 2000; Wilson, 2012). Normalized citations have

also been provided. But they were not used to calculate LL/BIC. 3. The total token (or sum frequency of keywords) of the 1997-2007 keyword corpus equals 10,327 and the total token of the

2008-2018 corpus equals 31,920. 4. An online calculator is also available in the following link (http://ucrel.lancs.ac.uk/llwizard.html ). To compute the LL and

BIC value of a keyword, simply put in the raw frequency information of a keyword and the size information of the two corpora.

5. BIC values below zero have all been omitted.

TABLE 2. Topics with decreasing interests

1997-2007 2008-2018

Type TopicsRaw Num

Norm.Num

Raw Num

Norm.Num LL BIC

Decrease with positive evidence (BIC> 2), strong evidence (BIC > 6.86) or very strong evidence (BIC >22.22) au French 204 104.2 295 60.2 65.08 54.43

au interlanguage 47 24 57 11.6 21.17 10.52

au Japanese 149 76.1 292 59.6 19.37 8.72

ad negotiation 50 25.5 69 14.1 17.64 6.98

au reading 259 132.3 583 119 17.26 6.61

au Spanish 273 139.4 621 126.8 17.09 6.43

au listening comprehension 39 19.9 49 10 16.50 5.85

au phonological awareness 31 15.8 35 7.1 15.71 5.06

au discourse 179 91.4 386 78.8 15.11 4.46

au specific language impairment 28 14.3 31 6.3 14.63 3.98

ad extrinsic motivation 5 2.6 0 0 14.09 3.44

au topic familiarity 9 4.6 3 0.6 13.54 2.89

ad oral proficiency 42 21.5 62 12.7 12.79 2.14

ad Quebec 12 6.1 7 1.4 12.73 2.08

Decrease with evidence (LL > 3.84)ad spelling 31 15.8 41 8.4 11.91 1.26

ad learner repair 7 3.6 2 0.4 11.31 0.66

ad negotiated interaction 7 3.6 2 0.4 11.31 0.66

ad language impairment 34 17.4 49 10 10.93 0.28

ad impairment 41 20.9 64 13.1 10.92 0.26

au focus-on-form 31 15.8 44 9 10.30 --

ad metaphor 23 11.7 28 5.7 10.29 --

ad conversational interaction 9 4.6 5 1 9.91 --

ad Firth & Wanger 8 4.1 4 0.8 9.51 --

ad immersion classroom 7 3.6 3 0.6 9.19 --

ad consonant 19 9.7 23 4.7 8.58 --

ad phonemic awareness 9 4.6 6 1.2 8.53 --

au immersion 49 25 89 18.2 8.41 --

ad regression analysis 20 10.2 26 5.3 7.94 --

ad phonological representation 13 6.6 13 2.7 7.87 --

au anxiety 47 24 86 17.6 7.86 --

au transfer 89 45.5 191 39 7.70 --

au integrative orientation 7 3.6 4 0.8 7.54 --

ad oral proficiency interview 23 11.7 33 6.7 7.47 --

ad nonword 20 10.2 27 5.5 7.38 --

au internet 27 13.8 42 8.6 7.25 --

au Non-native speakers 26 13.3 40 8.2 7.18 --

ad French immersion 10 5.1 9 1.8 6.93 --

ad noun phrase accessibility 5 2.6 2 0.4 6.83 --

ad comprehension strategies 4 2 1 0.2 6.83 --

au negative feedback 8 4.1 6 1.2 6.78 --

au aspect hypothesis 8 4.1 7 1.4 5.74 --

au processing capacity 6 3.1 4 0.8 5.69 --

ad disorder 14 7.2 18 3.7 5.68 --

ad expressive language delay 2 1 0 0 5.64 --

ad formulation processes 2 1 0 0 5.64 --

ad gating paradigm 2 1 0 0 5.64 --

ad mutual intelligibility 2 1 0 0 5.64 --

ad optimality theory 2 1 0 0 5.64 --

au literacy 64 32.7 138 28.2 5.40 --

au listening 89 45.5 204 41.6 5.31 --

ad content based instruction 7 3.6 6 1.2 5.14 --

au social context 15 7.7 21 4.3 5.13 --

au register 21 10.7 34 6.9 5.08 --

au language teaching 99 50.6 233 47.6 4.96 --

ad ambiguity resolution 4 2 2 0.4 4.75 --

ad comprehensible input 4 2 2 0.4 4.75 --

au postsecondary 15 7.7 22 4.5 4.64 --

ad determinant 6 3.1 5 1 4.55 --

au language contact 12 6.1 16 3.3 4.54 --

ad tense aspect morphology 3 1.5 1 0.2 4.51 --

au classroom research 7 3.6 7 1.4 4.24 --

au think aloud 20 10.2 34 6.9 4.22 --

ad phonological process 15 7.7 23 4.7 4.17 --

ad academic discourse 8 4.1 9 1.8 4.08 --

au metacognitive strategies 8 4.1 9 1.8 4.08 --

au zone of proximal development 9 4.6 11 2.2 4.00 --

ad self confidence 10 5.1 13 2.7 3.97 --

ad socialization 20 10.2 35 7.1 3.87 --

Notes: au = author-supplied-keyword; ad = keyword-from-abstracts; LL = Log-likelihood; BIC = Bayes Factor (Wilson, 2012).

TABLE 3. Topics without much change (LL < 3.84)

Type Topics

1997-2007 2008-2018

LL BICRaw Num

Norm.Num

Raw Num

Norm.Num

ad strategy use 36 18.4 74 15.1 3.83 --

au ultimate attainment 2 1 21 4.3 3.82 --

au heritage language 14 7.2 74 15.1 3.81 --

au L2 motivational self-system 1 0.5 15 3.1 3.75 --

au quantitative 60 30.6 243 49.6 3.71 --

au morphosyntax 6 3.1 40 8.2 3.71 --

au matrix language 6 3.1 6 1.2 3.63 --

au oral production 15 7.7 77 15.7 3.61 --

au negotiation of meaning 12 6.1 18 3.7 3.52 --

au interlanguage pragmatic 7 3.6 8 1.6 3.48 --

au phonological memory 7 3.6 8 1.6 3.48 --

ad reading acquisition 7 3.6 8 1.6 3.48 --

au TESOL 31 15.8 63 12.9 3.46 --

au American sign language 2 1 20 4.1 3.44 --

au online processing 2 1 20 4.1 3.44 --

au written corrective feedback 2 1 20 4.1 3.44 --

au structural equation model 11 5.6 60 12.2 3.40 --

ad cortex 4 2 3 0.6 3.39 --

ad international teaching assistant 4 2 3 0.6 3.39 --

au digital game 0 0 6 1.2 3.36 --

au incomplete acquisition 0 0 6 1.2 3.36 --

au language teacher identity 0 0 6 1.2 3.36 --

ad linguistic experience 0 0 6 1.2 3.36 --

ad perceived foreign accent 0 0 6 1.2 3.36 --

au possible selves 0 0 6 1.2 3.36 --

au quantitative research 0 0 6 1.2 3.36 --

au fluency 47 24 194 39.6 3.35 --

au Chinese as a second language 1 0.5 14 2.9 3.32 --

au concordancer 1 0.5 14 2.9 3.32 --

au language control 1 0.5 14 2.9 3.32 --

au intelligibility 14 7.2 23 4.7 3.26 --

ad nonnative speaker 24 12.3 47 9.6 3.13 --

au language switching 3 1.5 24 4.9 3.07 --

au self-regulation 3 1.5 24 4.9 3.07 --

au learning context 15 7.7 74 15.1 3.01 --

ad oral language 5 2.6 33 6.7 2.99 --

ad writing task 14 7.2 70 14.3 2.99 --

ad written production 15 7.7 26 5.3 2.99 --

au code switching 20 10.2 38 7.8 2.93 --

au communicative competence 20 10.2 38 7.8 2.93 --

au lexical bundle(s) 1 0.5 13 2.7 2.90 --

au P600 1 0.5 13 2.7 2.90 --

au nonword repetition 9 4.6 13 2.7 2.88 --

au universal grammar 9 4.6 13 2.7 2.88 --

au imitation 28 14.3 122 24.9 2.88 --

au Cantonese 17 8.7 31 6.3 2.88 --

au event related potential 4 2 28 5.7 2.85 --

au bilingual speech production 3 1.5 2 0.4 2.84 --

au distance language learning 3 1.5 2 0.4 2.84 --

ad keyword method 3 1.5 2 0.4 2.84 --

ad metalinguistic skill 3 1.5 2 0.4 2.84 --

au L2 Spanish 7 3.6 41 8.4 2.83 --

au conventional expression 0 0 5 1 2.80 --

au intelligent CALL 0 0 5 1 2.80 --

au intentional learning 0 0 5 1 2.80 --

au longitudinal research 0 0 5 1 2.80 --

au open educational resources 0 0 5 1 2.80 --

ad phonetic detail 0 0 5 1 2.80 --

au sociolinguistic variation 0 0 5 1 2.80 --

au storyline complexity 0 0 5 1 2.80 --

au Usage-based linguistics 0 0 5 1 2.80 --

ad vowel perception 0 0 5 1 2.80 --

au task based interaction 3 1.5 23 4.7 2.75 --

au Processability theory 2 1 18 3.7 2.72 --

ad proficient bilingual 2 1 18 3.7 2.72 --

au writing development 2 1 18 3.7 2.72 --

au grammar 123 62.8 319 65.1 2.66 --

ad variability 20 10.2 91 18.6 2.66 --

au word order 26 13.3 54 11 2.64 --

ad cohesion 11 5.6 18 3.7 2.59 --

au foreign accent 11 5.6 18 3.7 2.59 --

ad syllable 31 15.8 67 13.7 2.59 --

au heritage speaker 7 3.6 40 8.2 2.59 --

au generalization 17 8.7 32 6.5 2.58 --

au mediation 12 6.1 60 12.2 2.57 --

ad reading comprehension 51 26 120 24.5 2.56 --

ad linguistic knowledge 10 5.1 52 10.6 2.54 --

au automatization 1 0.5 12 2.4 2.49 --

au incidental acquisition 1 0.5 12 2.4 2.49 --

au language attrition 1 0.5 12 2.4 2.49 --

au simultaneous bilingual 1 0.5 12 2.4 2.49 --

au stress 35 17.9 78 15.9 2.47 --

au Turkish 15 7.7 71 14.5 2.46 --

ad down syndrome 4 2 4 0.8 2.42 --

ad syntactic awareness 4 2 4 0.8 2.42 --

ad talk in interaction 4 2 4 0.8 2.42 --

au feedback 81 41.4 303 61.9 2.41 --

au lexical decision 13 6.6 63 12.9 2.40 --

ad deficit hypothesis 2 1 1 0.2 2.38 --

ad functional category 2 1 1 0.2 2.38 --

au grammatical metaphor 2 1 1 0.2 2.38 --

ad grammatical morphology 2 1 1 0.2 2.38 --

ad interrater reliability 2 1 1 0.2 2.38 --

ad orthographic structure 2 1 1 0.2 2.38 --

au age of acquisition 7 3.6 39 8 2.35 --

au classroom discourse 8 4.1 12 2.4 2.35 --

ad cognitive process 10 5.1 51 10.4 2.34 --

au speaking 203 103.7 553 112.9 2.32 --

ad spontaneous speech 12 6.1 21 4.3 2.32 --

au input processing 7 3.6 10 2 2.29 --

ad lexical acquisition 5 2.6 6 1.2 2.29 --

ad long term retention 5 2.6 6 1.2 2.29 --

au translation 58 29.6 141 28.8 2.29 --

ad argument structure 6 3.1 8 1.6 2.27 --

au order of acquisition 6 3.1 8 1.6 2.27 --

ad self-repair 6 3.1 8 1.6 2.27 --

au call teacher education 0 0 4 0.8 2.24 --

ad developmental dyslexia 0 0 4 0.8 2.24 --

ad distributed practice 0 0 4 0.8 2.24 --

ad explicit memory 0 0 4 0.8 2.24 --

au first language attrition 0 0 4 0.8 2.24 --

ad language ideology 0 0 4 0.8 2.24 --

au learning analytics 0 0 4 0.8 2.24 --

ad lexical competition 0 0 4 0.8 2.24 --

au teacher autonomy 0 0 4 0.8 2.24 --

au virtual world 0 0 4 0.8 2.24 --

ad visual attention 0 0 4 0.8 2.24 --

au Italian 31 15.8 69 14.1 2.21 --

au recast 31 15.8 69 14.1 2.21 --

au picture naming 5 2.6 30 6.1 2.20 --

au teachers' belief 5 2.6 30 6.1 2.20 --

au cognate 12 6.1 58 11.8 2.19 --

au executive function 3 1.5 21 4.3 2.14 --

au lexical processing 3 1.5 21 4.3 2.14 --

au negation 3 1.5 21 4.3 2.14 --

au syntactic complexity 10 5.1 50 10.2 2.14 --

ad English vowel 1 0.5 11 2.2 2.10 --

ad number agreement 1 0.5 11 2.2 2.10 --

au L2 proficiency 21 10.7 91 18.6 2.09 --

au longitudinal study 23 11.7 49 10 2.06 --

ad complex word 2 1 16 3.3 2.05 --

au online interaction 2 1 16 3.3 2.05 --

ad adjective 12 6.1 57 11.6 2.00 --

au tense 40 20.4 95 19.4 1.88 --

au language processing 13 6.6 60 12.2 1.87 --

au implicit learning 3 1.5 20 4.1 1.85 --

au age of arrival 7 3.6 11 2.2 1.83 --

au critical discourse analysis 7 3.6 11 2.2 1.83 --

ad genre analysis 3 1.5 3 0.6 1.82 --

ad naming speed 3 1.5 3 0.6 1.82 --

ad variety of English 3 1.5 3 0.6 1.82 --

ad teacher education 28 14.3 114 23.3 1.80 --

au e-portfolio 6 3.1 9 1.8 1.76 --

au individual variation 6 3.1 9 1.8 1.76 --

au Dutch 37 18.9 145 29.6 1.74 --

au intercultural communicative competence 2 1 15 3.1 1.73 --

au bilingual development 1 0.5 10 2 1.72 --

ad natural language processing 1 0.5 10 2 1.72 --

au automaticity 5 2.6 7 1.4 1.71 --

ad consonant cluster 5 2.6 7 1.4 1.71 --

ad metacognitive awareness 5 2.6 7 1.4 1.71 --

ad self determination 5 2.6 7 1.4 1.71 --

ad syllable structure 5 2.6 7 1.4 1.71 --

au willingness to communicate 8 4.1 40 8.2 1.71 --

au dyadic interaction 4 2 5 1 1.71 --

au object clitics 4 2 5 1 1.71 --

ad relative clause 18 9.2 38 7.8 1.69 --

ad bilingual brain 0 0 3 0.6 1.68 --

au bilingual lexical access 0 0 3 0.6 1.68 --

au computer game 0 0 3 0.6 1.68 --

au concept based instruction 0 0 3 0.6 1.68 --

ad dual route 0 0 3 0.6 1.68 --

au executive attention 0 0 3 0.6 1.68 --

au grammatical processing 0 0 3 0.6 1.68 --

ad hand gesture(s) 0 0 3 0.6 1.68 --

ad language distance 0 0 3 0.6 1.68 --

au linguistic relativity 0 0 3 0.6 1.68 --

au linking adverbials 0 0 3 0.6 1.68 --

ad phonotactic probability 0 0 3 0.6 1.68 --

ad processing abilities 0 0 3 0.6 1.68 --

ad semantic facilitation 0 0 3 0.6 1.68 --

ad sensitive period 0 0 3 0.6 1.68 --

ad speech segmentation 0 0 3 0.6 1.68 --

ad symbolic competence 0 0 3 0.6 1.68 --

ad tone perception 0 0 3 0.6 1.68 --

au translation ambiguity 0 0 3 0.6 1.68 --

ad language learning strategies 14 7.2 28 5.7 1.68 --

au L2 writing 12 6.1 55 11.2 1.66 --

ad identities 33 16.9 78 15.9 1.61 --

au pronunciation 38 19.4 147 30 1.59 --

au think aloud protocol(s) 11 5.6 21 4.3 1.58 --

ad individual difference 24 12.3 98 20 1.58 --

ad language comprehension 3 1.5 19 3.9 1.58 --

au convergence 4 2 23 4.7 1.51 --

ad learner autonomy 4 2 23 4.7 1.51 --

au oral fluency 4 2 23 4.7 1.51 --

au noticing 26 13.3 60 12.2 1.49 --

au explicit knowledge 6 3.1 31 6.3 1.48 --

ad phonemes 14 7.2 29 5.9 1.44 --

au bimodal 2 1 14 2.9 1.43 --

au accent 38 19.4 93 19 1.42 --

au retention 32 16.3 77 15.7 1.37 --

au bilingual processing 1 0.5 9 1.8 1.36 --

ad subordinate clause 1 0.5 9 1.8 1.36 --

ad English bilingual 24 12.3 96 19.6 1.34 --

au metacognition 6 3.1 10 2 1.34 --

au language proficiency 51 26 130 26.5 1.32 --

ad academic English 3 1.5 18 3.7 1.32 --

au mental lexicon 3 1.5 18 3.7 1.32 --

ad subject verb agreement 3 1.5 18 3.7 1.32 --

ad grammaticality judgment 14 7.2 60 12.2 1.29 --

au accentedness 6 3.1 30 6.1 1.28 --

ad effect size 5 2.6 26 5.3 1.27 --

ad free recall 5 2.6 8 1.6 1.25 --

ad processing skill 5 2.6 8 1.6 1.25 --

au English 717 366.2 2323 474.3 1.22 --

ad corpus based study 2 1 2 0.4 1.21 --

ad diglossia 2 1 2 0.4 1.21 --

ad linguistic diversity 2 1 2 0.4 1.21 --

ad linguistic interdependence 2 1 2 0.4 1.21 --

ad parsing strategies 2 1 2 0.4 1.21 --

ad overt subject 4 2 6 1.2 1.17 --

au program evaluation 4 2 6 1.2 1.17 --

au self-determination theory 4 2 6 1.2 1.17 --

ad syntactic transfer 4 2 6 1.2 1.17 --

au retrieval 20 10.2 46 9.4 1.17 --

au gaming 2 1 13 2.7 1.14 --

au incidental learning 2 1 13 2.7 1.14 --

au planning time 2 1 13 2.7 1.14 --

au classroom based research 3 1.5 4 0.8 1.13 --

ad reading disability 3 1.5 4 0.8 1.13 --

au theory of mind 3 1.5 4 0.8 1.13 --

ad age onset 0 0 2 0.4 1.12 --

au aptitude treatment interaction 0 0 2 0.4 1.12 --

ad aspect marking 0 0 2 0.4 1.12 --

ad categorical perception 0 0 2 0.4 1.12 --

au content based language teaching 0 0 2 0.4 1.12 --

au embodied cognition 0 0 2 0.4 1.12 --

ad interactional routine 0 0 2 0.4 1.12 --

au intertextuality 0 0 2 0.4 1.12 --

ad lexical ambiguity 0 0 2 0.4 1.12 --

au online language teaching 0 0 2 0.4 1.12 --

au online tutoring 0 0 2 0.4 1.12 --

ad phonetic categorization 0 0 2 0.4 1.12 --

ad word segmentation 0 0 2 0.4 1.12 --

au language play 7 3.6 13 2.7 1.11 --

ad receptive vocabulary 6 3.1 29 5.9 1.09 --

au Vygotsky 11 5.6 23 4.7 1.08 --

au aptitude 15 7.7 62 12.7 1.08 --

au activity theory 3 1.5 17 3.5 1.07 --

au grammatical accuracy 5 2.6 25 5.1 1.07 --

ad language related episode 5 2.6 25 5.1 1.07 --

au language anxiety 14 7.2 31 6.3 1.03 --

au information structure 1 0.5 8 1.6 1.02 --

au language teacher preparation 1 0.5 8 1.6 1.02 --

au learner proficiency 1 0.5 8 1.6 1.02 --

ad maturational constraint 1 0.5 8 1.6 1.02 --

ad narrative inquiry 1 0.5 8 1.6 1.02 --

au oral corrective feedback 1 0.5 8 1.6 1.02 --

au Self-regulated learning 1 0.5 8 1.6 1.02 --

au vocabulary teaching 1 0.5 8 1.6 1.02 --

au word recognition 31 15.8 77 15.7 1.02 --

au language socialization 10 5.1 21 4.3 0.96 --

ad segmentation 10 5.1 21 4.3 0.96 --

ad classroom anxiety 8 4.1 16 3.3 0.96 --

au communication strategies 8 4.1 16 3.3 0.96 --

ad productive vocabulary 8 4.1 16 3.3 0.96 --

au alignment 10 5.1 43 8.8 0.95 --

au factor analysis 10 5.1 43 8.8 0.95 --

au learning motivation 10 5.1 43 8.8 0.95 --

au vocabulary acquisition 16 8.2 64 13.1 0.89 --

au French as a second language 5 2.6 9 1.8 0.88 --

au videoconferencing 5 2.6 9 1.8 0.88 --

au word association 5 2.6 9 1.8 0.88 --

au EFL context 5 2.6 24 4.9 0.88 --

au incidental vocabulary learning 2 1 12 2.4 0.88 --

au language attitude 2 1 12 2.4 0.88 --

au writing 173 88.4 492 100.4 0.88 --

au corpus 66 33.7 232 47.4 0.87 --

au vocabulary knowledge 23 11.7 88 18 0.86 --

au wh questions 4 2 20 4.1 0.86 --

au heritage language learner 3 1.5 16 3.3 0.85 --

ad learning behavior 3 1.5 16 3.3 0.85 --

ad metalinguistic awareness 3 1.5 16 3.3 0.85 --

au globalization 9 4.6 19 3.9 0.84 --

au L1 transfer 9 4.6 19 3.9 0.84 --

au personality 9 4.6 19 3.9 0.84 --

au proficiency 260 132.8 752 153.5 0.84 --

au language policy 7 3.6 14 2.9 0.84 --

au homestay 4 2 7 1.4 0.77 --

au student attitude 4 2 7 1.4 0.77 --

au grammar instruction 10 5.1 22 4.5 0.76 --

ad social interaction 13 6.6 30 6.1 0.74 --

au concordancing 1 0.5 7 1.4 0.71 --

au English for specific purposes 1 0.5 7 1.4 0.71 --

au error analysis 1 0.5 7 1.4 0.71 --

au instructed second language acquisition 1 0.5 7 1.4 0.71 --

au L2 sentence processing 1 0.5 7 1.4 0.71 --

ad lexical selection 1 0.5 7 1.4 0.71 --

au listening strategies 1 0.5 7 1.4 0.71 --

au learners' perception 5 2.6 23 4.7 0.71 --

au sentence comprehension 5 2.6 23 4.7 0.71 --

au pragmatic competence 11 5.6 25 5.1 0.69 --

au e-learning 18 9.2 44 9 0.68 --

au incidental vocabulary acquisition 3 1.5 5 1 0.67 --

au needs analysis 3 1.5 5 1 0.67 --

ad referring expression 3 1.5 5 1 0.67 --

ad selective attention 3 1.5 5 1 0.67 --

ad linguistic awareness 4 2 19 3.9 0.67 --

au orthography 19 9.7 47 9.6 0.65 --

ad speech perception 7 3.6 30 6.1 0.65 --

ad error type 9 4.6 20 4.1 0.65 --

au idiom 9 4.6 20 4.1 0.65 --

au reading strategies 9 4.6 20 4.1 0.65 --

ad imagery 2 1 11 2.2 0.64 --

ad lexical tone 2 1 11 2.2 0.64 --

ad online chat 2 1 11 2.2 0.64 --

ad revised hierarchical model 2 1 11 2.2 0.64 --

au systemic functional linguistics 2 1 11 2.2 0.64 --

ad teacher feedback 2 1 11 2.2 0.64 --

au nouns 55 28.1 150 30.6 0.62 --

ad auditory lexical decision 1 0.5 1 0.2 0.61 --

au Russian 33 16.9 87 17.8 0.59 --

ad bilingual word recognition 2 1 3 0.6 0.59 --

au interlingual homograph 2 1 3 0.6 0.59 --

ad morpho syntactic 2 1 3 0.6 0.59 --

ad output hypothesis 2 1 3 0.6 0.59 --

ad professional identity 2 1 3 0.6 0.59 --

ad serial recall 2 1 3 0.6 0.59 --

au social presence 2 1 3 0.6 0.59 --

ad stop consonant 2 1 3 0.6 0.59 --

au repetition 42 21.5 113 23.1 0.58 --

au morphology 37 18.9 99 20.2 0.55 --

ad academic language 5 2.6 22 4.5 0.55 --

ad animacy 5 2.6 22 4.5 0.55 --

au writing instruction 5 2.6 22 4.5 0.55 --

au input 115 58.7 328 67 0.54 --

au language use 60 30.6 166 33.9 0.53 --

au pragmatics 15 7.7 57 11.6 0.53 --

au sentence processing 15 7.7 37 7.6 0.53 --

au motivation 99 50.6 281 57.4 0.52 --

au cross linguistic influence 9 4.6 36 7.3 0.50 --

au concreteness 6 3.1 13 2.7 0.49 --

au vowel 27 13.8 97 19.8 0.49 --

ad lexical knowledge 9 4.6 21 4.3 0.48 --

au neuroimaging 4 2 8 1.6 0.48 --

ad object clitic 4 2 8 1.6 0.48 --

au inflection 23 11.7 60 12.2 0.47 --

au bilingual education 3 1.5 14 2.9 0.46 --

au Portuguese 8 4.1 32 6.5 0.45 --

au automated writing evaluation 1 0.5 6 1.2 0.44 --

ad coh-metrix 1 0.5 6 1.2 0.44 --

ad cross language transfer 1 0.5 6 1.2 0.44 --

ad electrophysiological 1 0.5 6 1.2 0.44 --

ad language analytic ability 1 0.5 6 1.2 0.44 --

au language mixing 1 0.5 6 1.2 0.44 --

au lexical sophistication 1 0.5 6 1.2 0.44 --

au online instruction 1 0.5 6 1.2 0.44 --

ad picture word interference 1 0.5 6 1.2 0.44 --

au thinking for speaking 1 0.5 6 1.2 0.44 --

ad verb noun collocation 1 0.5 6 1.2 0.44 --

au frequency effect 2 1 10 2 0.43 --

au L2 phonology 2 1 10 2 0.43 --

au second language speech 2 1 10 2 0.43 --

ad self-concept 2 1 10 2 0.43 --

ad balanced bilingual 7 3.6 16 3.3 0.43 --

au critical period 7 3.6 16 3.3 0.43 --

au minority language 7 3.6 16 3.3 0.43 --

au implicit knowledge 5 2.6 21 4.3 0.40 --

ad pronoun 22 11.2 58 11.8 0.39 --

ad morpheme 14 7.2 52 10.6 0.39 --

au reliability 14 7.2 52 10.6 0.39 --

au semantics 14 7.2 52 10.6 0.39 --

au Korean 52 26.6 177 36.1 0.38 --

ad autism 5 2.6 11 2.2 0.38 --

ad discourse analysis 17 8.7 44 9 0.38 --

au web based 12 6.1 45 9.2 0.37 --

au phonology 25 12.8 67 13.7 0.36 --

au fMRI 3 1.5 6 1.2 0.36 --

au reactivity 3 1.5 6 1.2 0.36 --

ad student motivation 3 1.5 6 1.2 0.36 --

ad word translation 3 1.5 6 1.2 0.36 --

ad native language 51 26 143 29.2 0.35 --

au simultaneous bilingualism 4 2 17 3.5 0.35 --

ad sociocognition 4 2 17 3.5 0.35 --

au gender agreement 9 4.6 22 4.5 0.34 --

au language learning motivation 9 4.6 22 4.5 0.34 --

ad speech act 9 4.6 22 4.5 0.34 --

au classroom interaction 20 10.2 53 10.8 0.34 --

au reaction time 13 6.6 48 9.8 0.33 --

au memory 71 36.3 237 48.4 0.33 --

au English as a second language 64 32.7 182 37.2 0.32 --

au L1 influence 6 3.1 14 2.9 0.32 --

au syntax 47 24 132 26.9 0.31 --

au Hebrew 10 5.1 25 5.1 0.31 --

ad translation equivalent 10 5.1 25 5.1 0.31 --

ad past tense 16 8.2 42 8.6 0.30 --

au turn taking 3 1.5 13 2.7 0.30 --

au variation 61 31.2 174 35.5 0.29 --

au sociocultural theory 7 3.6 27 5.5 0.28 --

au students' perception 12 6.1 44 9 0.28 --

au writing process 5 2.6 20 4.1 0.28 --

au interactional competence 7 3.6 17 3.5 0.28 --

ad mother tongue 7 3.6 17 3.5 0.28 --

au competition model 4 2 9 1.8 0.27 --

au interactional feedback 4 2 9 1.8 0.27 --

au tone 30 15.3 83 16.9 0.27 --

ad verb(s) 165 84.3 487 99.4 0.26 --

ad speaking rate 2 1 9 1.8 0.25 --

au task effects 2 1 9 1.8 0.25 --

au L2 processing 8 4.1 30 6.1 0.24 --

au lexical access 8 4.1 30 6.1 0.24 --

ad acculturation 2 1 4 0.8 0.24 --

ad corpus consultation 2 1 4 0.8 0.24 --

au critical pedagogy 2 1 4 0.8 0.24 --

ad induced involvement 2 1 4 0.8 0.24 --

ad recognition memory 2 1 4 0.8 0.24 --

ad semantic interference 2 1 4 0.8 0.24 --

au speaking assessment 2 1 4 0.8 0.24 --

ad task induced involvement 2 1 4 0.8 0.24 --

au language skill 24 12.3 66 13.5 0.24 --

au L2 vocabulary learning 4 2 16 3.3 0.22 --

au caption 5 2.6 12 2.4 0.22 --

ad identity construction 5 2.6 12 2.4 0.22 --

au word reading 17 8.7 46 9.4 0.22 --

au chunking 1 0.5 5 1 0.21 --

au critical period hypothesis 1 0.5 5 1 0.21 --

ad linguistic constraint 1 0.5 5 1 0.21 --

au metacognitive knowledge 1 0.5 5 1 0.21 --

au phraseology 1 0.5 5 1 0.21 --

au speech rhythm 1 0.5 5 1 0.21 --

au summary writing 1 0.5 5 1 0.21 --

ad Williams syndrome 1 0.5 5 1 0.21 --

au language aptitude 10 5.1 26 5.3 0.21 --

ad short term memory 11 5.6 29 5.9 0.20 --

au scaffolding 10 5.1 36 7.3 0.19 --

au modified output 6 3.1 15 3.1 0.19 --

au L2 Chinese 5 2.6 19 3.9 0.18 --

au language assessment 5 2.6 19 3.9 0.18 --

au peer interaction 5 2.6 19 3.9 0.18 --

au vocabulary size 14 7.2 49 10 0.17 --

ad dependencies 3 1.5 12 2.4 0.17 --

au grounded theory 3 1.5 12 2.4 0.17 --

au metalinguistic knowledge 3 1.5 12 2.4 0.17 --

ad voice onset time 3 1.5 12 2.4 0.17 --

au processing instruction 7 3.6 18 3.7 0.17 --

au suprasegmental 7 3.6 18 3.7 0.17 --

au cognate status 3 1.5 7 1.4 0.16 --

ad homograph 3 1.5 7 1.4 0.16 --

au learning disabilities 3 1.5 7 1.4 0.16 --

ad verb morphology 3 1.5 7 1.4 0.16 --

au categorization 12 6.1 42 8.6 0.15 --

au clitics 9 4.6 24 4.9 0.14 --

ad cognitive linguistics 4 2 10 2 0.12 --

ad lexical development 4 2 10 2 0.12 --

au English for academic purposes 11 5.6 30 6.1 0.12 --

ad validity 37 18.9 107 21.8 0.12 --

au exposure 71 36.3 230 47 0.12 --

ad amotivation 1 0.5 2 0.4 0.12 --

ad contrastive analysis 1 0.5 2 0.4 0.12 --

ad critical literacy 1 0.5 2 0.4 0.12 --

ad empirical validation 1 0.5 2 0.4 0.12 --

ad human brain 1 0.5 2 0.4 0.12 --

ad inflected word 1 0.5 2 0.4 0.12 --

ad inhibitory process 1 0.5 2 0.4 0.12 --

ad phonetic perception 1 0.5 2 0.4 0.12 --

ad phonological working memory 1 0.5 2 0.4 0.12 --

ad prefrontal cortex 1 0.5 2 0.4 0.12 --

au input frequency 2 1 8 1.6 0.11 --

au narrative structure 2 1 8 1.6 0.11 --

ad neighborhood density 2 1 8 1.6 0.11 --

au Pinyin 2 1 8 1.6 0.11 --

au pre-task planning 2 1 8 1.6 0.11 --

ad sociolinguistic competence 2 1 8 1.6 0.11 --

au syntactic priming 2 1 8 1.6 0.11 --

ad written feedback 2 1 8 1.6 0.11 --

au attrition 11 5.6 38 7.8 0.11 --

au gestures 15 7.7 42 8.6 0.11 --

ad word frequency 15 7.7 42 8.6 0.11 --

au corpus linguistics 5 2.6 13 2.7 0.11 --

au inflectional morphology 5 2.6 13 2.7 0.11 --

au lexical aspect 5 2.6 13 2.7 0.11 --

au pair work 5 2.6 13 2.7 0.11 --

au conversation analysis 18 9.2 51 10.4 0.10 --

ad genre 20 10.2 57 11.6 0.10 --

au language transfer 5 2.6 18 3.7 0.09 --

au word/vocabulary learning 48 24.5 156 31.8 0.09 --

ad cognitive development 6 3.1 16 3.3 0.09 --

ad consciousness 6 3.1 16 3.3 0.09 --

au dyslexia 6 3.1 16 3.3 0.09 --

ad language testing 7 3.6 19 3.9 0.08 --

ad teachers' perception 7 3.6 19 3.9 0.08 --

au vocabulary 166 84.8 500 102.1 0.08 --

au meta-analysis 8 4.1 22 4.5 0.08 --

au monitoring 14 7.2 47 9.6 0.07 --

ad age difference 3 1.5 11 2.2 0.07 --

au input enhancement 3 1.5 11 2.2 0.07 --

au reading fluency 3 1.5 11 2.2 0.07 --

au intonation 11 5.6 31 6.3 0.07 --

ad affective variables 2 1 5 1 0.06 --

ad aphasia 2 1 5 1 0.06 --

ad discourse marker 2 1 5 1 0.06 --

ad education policy 2 1 5 1 0.06 --

ad metadiscourse 2 1 5 1 0.06 --

au null object 2 1 5 1 0.06 --

ad sentence production 2 1 5 1 0.06 --

ad derivational morphology 1 0.5 4 0.8 0.06 --

ad dyslexics 1 0.5 4 0.8 0.06 --

ad episodic memory 1 0.5 4 0.8 0.06 --

ad interactive activation model 1 0.5 4 0.8 0.06 --

ad language speech perception 1 0.5 4 0.8 0.06 --

ad lexical coverage 1 0.5 4 0.8 0.06 --

au multicompetence 1 0.5 4 0.8 0.06 --

ad social class 1 0.5 4 0.8 0.06 --

ad subject object ambiguities 1 0.5 4 0.8 0.06 --

au task motivation 1 0.5 4 0.8 0.06 --

ad television program 1 0.5 4 0.8 0.06 --

ad word family 1 0.5 4 0.8 0.06 --

au explicit correction 4 2 14 2.9 0.05 --

au humor 4 2 14 2.9 0.05 --

au phonological short-term memory 4 2 14 2.9 0.05 --

ad speech rate 8 4.1 27 5.5 0.05 --

au L3 acquisition 3 1.5 8 1.6 0.05 --

ad plasticity 3 1.5 8 1.6 0.05 --

ad processing speed 3 1.5 8 1.6 0.05 --

ad world Englishes 3 1.5 8 1.6 0.05 --

au language production 13 6.6 43 8.8 0.05 --

au production 187 95.5 568 116 0.04 --

au narrative 59 30.1 188 38.4 0.04 --

au oral communication 5 2.6 17 3.5 0.04 --

au Swedish 15 7.7 49 10 0.04 --

au collaborative dialogue 5 2.6 14 2.9 0.04 --

au compounds 5 2.6 14 2.9 0.04 --

au frequency 108 55.2 327 66.8 0.03 --

ad qualitative analysis 16 8.2 52 10.6 0.03 --

ad self assessment 8 4.1 23 4.7 0.03 --

ad noun phrase 15 7.7 44 9 0.03 --

au form focused instruction 9 4.6 26 5.3 0.03 --

au prosody 12 6.1 35 7.1 0.03 --

au language development 40 20.4 120 24.5 0.03 --

au Arabic 24 12.3 77 15.7 0.03 --

ad bilingual memory 2 1 7 1.4 0.02 --

ad garden path 2 1 7 1.4 0.02 --

au null subject 2 1 7 1.4 0.02 --

ad reading aloud 2 1 7 1.4 0.02 --

au aging 51 26 154 31.4 0.02 --

ad Finnish 8 4.1 26 5.3 0.02 --

ad syntactic structure 8 4.1 26 5.3 0.02 --

au lexicon 22 11.2 70 14.3 0.01 --

ad cross linguistic transfer 3 1.5 10 2 0.01 --

au semantic priming 3 1.5 10 2 0.01 --

au gesture 18 9.2 54 11 0.01 --

au grammatical gender 9 4.6 29 5.9 0.01 --

ad grammatical knowledge 9 4.6 29 5.9 0.01 --

au agency 16 8.2 48 9.8 0.01 --

ad case study 50 25.5 152 31 0.01 --

ad identity 49 25 154 31.4 0.01 --

au multimedia 12 6.1 36 7.3 0.01 --

ad formulaic sequence 4 2 13 2.7 0.01 --

au determiner 11 5.6 33 6.7 0.01 --

ad academic writing 12 6.1 38 7.8 0.01 --

au lexical representation 8 4.1 24 4.9 0.01 --

au vocabulary development 7 3.6 21 4.3 0.00 --

ad socioeconomic status 6 3.1 18 3.7 0.00 --

au writing proficiency 6 3.1 18 3.7 0.00 --

ad intrinsic motivation 5 2.6 15 3.1 0.00 --

ad language awareness 4 2 12 2.4 0.00 --

au pragmatic development 4 2 12 2.4 0.00 --

ad sentence context 4 2 12 2.4 0.00 --

ad spoken word recognition 4 2 12 2.4 0.00 --

ad brain potentials 3 1.5 9 1.8 0.00 --

ad cognitive factor 3 1.5 9 1.8 0.00 --

ad deaf children 3 1.5 9 1.8 0.00 --

au metalinguistic feedback 3 1.5 9 1.8 0.00 --

au phrasal verb 3 1.5 9 1.8 0.00 --

au situated learning 3 1.5 9 1.8 0.00 --

au constructivism 2 1 6 1.2 0.00 --

au lexical inferencing 2 1 6 1.2 0.00 --

au self-directed learning 2 1 6 1.2 0.00 --

au teacher knowledge 2 1 6 1.2 0.00 --

ad video game 2 1 6 1.2 0.00 --

ad dictionary use 1 0.5 3 0.6 0.00 --

ad embodiment 1 0.5 3 0.6 0.00 --

ad implicit memory 1 0.5 3 0.6 0.00 --

au interactive learning 1 0.5 3 0.6 0.00 --

au L2 morphosyntax 1 0.5 3 0.6 0.00 --

ad memory research 1 0.5 3 0.6 0.00 --

au multimodal texts 1 0.5 3 0.6 0.00 --

au polysemy 1 0.5 3 0.6 0.00 --

au structural distance 1 0.5 3 0.6 0.00 --

ad teachability 1 0.5 3 0.6 0.00 --

au virtual environment 1 0.5 3 0.6 0.00 --

au web based instruction 1 0.5 3 0.6 0.00 --

au gloss 18 9.2 56 11.4 0.00 --

au speech production 14 7.2 43 8.8 0.00 --

ad qualitative 124 63.3 384 78.4 0.00 --

au interference 19 9.7 59 12 0.00 --

au German 89 45.5 275 56.1 0.00 --