Nominalization as Grammatical Metaphors in the TOEFL Listening Module: A Systemic Functional Grammar Approach

Introduction
Systemic Functional Linguistics emphasizes the communicative function of language and the impact of context. Academic discourse is influenced by the use of Grammarical Metaphors (GMs), particularly nominalization. Consequently, familiarity with SFL concepts—particularly grammatical metaphors—is essential for all individuals involved in foreign language education, including teachers, textbook authors, and advanced learners who want to use the foreign Language in academic or professional settings such as business or diplomatic missions, must have a basic understanding of SFL principles, particularly grammatical metaphors like nominalization. As a result of the rising demand for English proficiency among universities and institutions worldwide, there has been heightened demand globally for exams such as TOEFL. Besides their general language ability, the tests evaluate candidates' aptitude for dealing with academic language that typically exhibits high-density words and intricate phrases as well as a higher ratio of nouns to verbs. Considering that grammatical metaphor is one of the most important features of academic and scientific discourse (Halliday, 1985, 1988, 2004; Devrim, 2015) and that nominal density is higher than verbal density in scientific language (Biber & Gray, 2021), the inclusion of SFG concepts—particularly nominalization—within TOEFL preparation materials could help learners more effectively grasp the structural features of academic texts. In practice, this means recognizing that academic writing typically employs complex clauses, lexical density, and a higher ratio of nouns to verbs due to nominalization. In other words, the more a text employs grammatical metaphor, the closer its structural and stylistic features are to academic discourse. Therefore, the present study asks two key questions: (1) to what extent nominalization is employed in the listening sections of the TOEFL iBT books, and (2) how such instances of grammatical metaphors are represented.
 
Literature Review
Within the framework of Systemic Functional Grammar (SFG), considerable attention has been devoted to the study of grammatical metaphor, particularly nominalization, considering its pivotal role in academic discourse. A number of seminal works have underscored the theoretical and pedagogical importance of this concept. For instance, Simon-Vandenbergen et al. (2003), in their comprehensive handbook, provide both theoretical insights and practical applications of grammatical metaphor from an SFL perspective, thereby offering an invaluable resource for researchers. Building on this foundation, Heyvaert (2011) further explores nominalization within the SFL framework, drawing on illustrative examples from Halliday (1994:353), Ravelli (1988:134), Matthiessen (1995:678), and Halliday and Matthiessen (1999:244) to clarify the systematic nature and varieties of nominalization, including verbal and adjectival types. The role played by nominalization towards academic success was also emphasized by applied linguistics research. Thompson (2009) analyzed the corpus of a sample of ten master’s theses written by non-natives employed in An Introduction to Applied Linguistics: Concepts and Skills (Swann et al., 2010). His research points to the prominent role played by grammatical metaphor towards the creation of knowledge building and the quality of the academic text. Citing Christie and Martin (1997), Thompson asserts that non-natives’ proficiency towards the use of grammatical metaphor goes closely together with their academic success. This joins the same line of thought as the present study. Also, Corpus-based studies show the extensive use of nominalization in scholarly texts. Holtz (2009), comparing a corpus of 49 scientific articles on four disciplines (including 420,000 words) found that nominalization was strongly indicative of informational density and text complexity. His study confirms that nominalization is a widespread feature of academic discourse. From a theoretical standpoint, SFL offers two complementary models for analyzing grammatical metaphor: the semantic and the stratified perspectives. Devrim (2015) proposed an integrative model that combines these approaches, conceptualizing grammatical metaphor as the result of a tension between ideational (experiential and logical) and interpersonal meanings within the lexico-grammar semantics. Although his framework provides valuable insights for pedagogy, it does not explicitly address textual metaphor. More recently, Liardet (2016) used Halliday (1993) and Martin (2008) to conduct an extensive study into the prevalence of nominalization within the academic texts produced by Chinese learners. Based on a corpus of 520 texts collected over the first four semesters of university study (see Liardet, 2013, 2014, 2015), the study reveals the development of nominalization through the course of learner writing and broader disciplinary text trends. These studies individually verified the predominance of nominalization both as a linguistic resource employed to construct scientific text and a marker of university-level scholarly literacy. There remains, however, little research on the extent and ratio of nominalization on standardized language proficiency tests such as the TOEFL, particularly the listening section. This gap is the immediate object of this research.
                                
Methodology
The present study focuses on the listening section of the TOEFL iBT, examining nominalization as a type of experiential grammatical metaphor. The corpus comprises 84 listening texts (lectures and conversations) drawn from three official TOEFL preparation books published by the Educational Testing Service (ETS): 1- The Official Guide to the TOEFL Test (including 4 tests), 2- Official TOEFL iBT Tests, Vol. 1 (including 5 tests), 3- Official TOEFL iBT Tests, Vol. 2 (including 5 tests). These materials were chosen because they are published by Educational Testing Service, unlike commercial preparation books (e.g., Cambridge, Oxford, Barron’s, Kaplan), which explicitly state that they are not endorsed by ETS. Each test includes 4–6 lectures (500–700 words each) and 2–3 conversations, providing a balanced dataset of academic discourse and interactive exchanges.
The analysis adopted a descriptive–analytical approach, grounded in SFG theory of grammatical metaphor (Halliday, 1994; Halliday & Matthiessen, 1999; Taverniers, 2003). Two categories of nominalization were examined: 1- Verbal nominalization, 2- Adjectival nominalization. Only clauses representing non-congruent, metaphorical realizations of meaning were included. Following Ravelli (1999) and Yang (2020), inaccurate or borderline cases were excluded. Specifically, technical terms (e.g., hopping genes, resistance genes), derived nouns with suffixes such as -ment (e.g., environment, experiment, apartment), and simple cases of conversion that did not compress both form and meaning were omitted. It is notable that clause by clause of the 14 tests including 84 texts (both conversation and lecture of listening module) were identified and analyzed. Two diagnostic tools were applied to verify metaphorical status: (1) the derivational test, which identifies nominal forms through morphological affixation (e.g., -tion, -ness, -er), and (2) the minimal grammatical pair test, which contrasts metaphorical forms with their congruent verbal or adjectival counterparts. The chi-square test and t-test were used to analyze the data.
 
Data Analysis
First, the listening transcripts were segmented into clauses. Then, instances of nominalization were identified, their congruent (literal) realizations proposed, and their frequency recorded. Separate analyses were conducted for lectures and conversations texts to allow comparison. Finally, the frequency distributions were examined to determine the extent and manner in which nominalization occurs across the two discourse types. To illustrate the analytical framework, consider the following sequence (Liardet, 2016):

Because more people are immigrating to Sydney, properties cost more money.
Due to increased immigration to Sydney, properties cost more money.
Sydney’s immigration growth has led to increased property costs.

While sentence A maintains a congruent structure (participants are noun phrases, and verbs function as processes), B and C demonstrate increasing levels of grammatical metaphor through nominalization (immigration, growth, costs) and abstract clause structuring. Although logical metaphor (e.g., has led to) falls outside this study's scope, the progression exemplifies how experiential meaning becomes increasingly condensed and abstract through nominalization. The clause was adopted as the unit of analysis, consistent with SFG tradition (Halliday & Matthiessen, 2014). All instances of verbal and adjectival nominalizations were identified and counted, with ambiguous forms (e.g., -ing, -er) only retained when they met established metaphorical criteria.
 
Analysis of Data from the Official Guide to the TOEFL iBT Test
The Official Guide to the TOEFL Test includes four complete tests, each containing six listening texts—comprising 10 conversations and 14 lectures. Following clause-level analysis, instances of experiential grammatical metaphor through nominalization were identified, and their congruent, literal counterparts were proposed. Two examples illustrate this process:
Example A – Verbal Nominalization
In the following clause, the verb apply is nominalized as application, creating an incongruent, metaphorical structure:
(A-1) Did you, um, have a chance to look at my grad school application…
(A-2) Did you have a chance to look at my paper by which I want to apply to graduate school…
According to Systemic Functional Grammar (SFG), since apply is a process typically realized as a verbal group, its realization as a nominal group (application) constitutes a grammatical metaphor.
Example B – Adjectival Nominalization
In this case, the adjective good is nominalized as goodness, shifting from a quality to a “thing,” which results in a metaphorical construction:
(B-1) …If we’re going to discuss goodness and …
(B-2) …If we’re going to discuss what makes an individual good and …
Here, goodness represents a metaphorical and incongruent form of the adjective good. The second clause provides its literal, congruent expression. This transformation reflects adjectival nominalization—another form of experiential grammatical metaphor. A total of 504 instances of nominalized grammatical metaphors were identified in The Official Guide to the TOEFL Test. of these, 117 occurred in the conversation sections and 387 in the lecture sections. These findings support the hypothesis that conversation texts retain structural features of spoken discourse, while lecture texts display characteristics more typical of written academic language. This pattern aligns with prior research, which suggests that experiential grammatical metaphors occur more frequently in formal, written texts than in spontaneous spoken discourse (Devrim, 2015). A summary of the findings from The Official Guide to the TOEFL Test is presented in Table 1.
 
Table 1: Total Frequency of Types of Grammatical Metaphors of Nominalization in Official Guide to the TOEFL iBT




Total Frequency of Metaphors


Adjectival Nominalization


Verbal Nominalization


Official Guide to the TOEFL iBT




117


6


111


Conversations




387


41


346


Lectures




504


47


457


Total Frequency




 
The following Table 2 shows the frequency of grammatical metaphors involving nominalization in the listening sections of the four tests included in the Official Guide to the TOEFL Test.
 
Table 2: Frequency of Grammatical Metaphors of Nominalization in the Listening Sections of the Four TOEFL Practice Tests in Official Guide to the TOEFL iBT




Total Frequency of Metaphors


Lectures


Conversations


Test Number




127


81


46


Test 1




102


87


15


Test 2




142


118


24


Test 3




133


101


32


Test 4




 
Data Analysis of Official TOEFL iBT Tests Volume 1
Official TOEFL iBT Tests Volume 1 comprises five complete tests, each containing six listening texts (lectures and conversations). This book includes 30 listening texts in total, consisting of 11 conversations and 19 lectures. Analysis revealed 717 instances of grammatical metaphor through nominalization: 177 in conversation texts and 540 in lecture texts. These findings further support the hypothesis that lecture sections exhibit a higher frequency of nominalization metaphors, aligning more closely with the features of written academic discourse. The distribution of grammatical metaphors identified in Volume 1 is summarized in Table 3.
 
 
 
 
 
 
 
Table 3: Total Frequency of Types of Grammatical Metaphors of Nominalization in Official TOEFL iBT Tests Volume 1




Total Frequency of Metaphors


Adjectival Nominalization


Verbal Nominalization


Official TOEFL iBT Tests Volume 1




177


9


168


Conversations




540


45


495


Lectures




717


54


663


Total Frequency




 
Based on the data presented in Table 4, it is evident that, across the five tests in TOEFL Official Tests Volume 1, the frequency of grammatical metaphors involving nominalization is consistently higher in lecture texts compared to conversation texts.
 
Table 4: Frequency of Grammatical Metaphors of Nominalization in the Listening Sections of Official TOEFL iBT Tests Volume 1




Total Frequency of Metaphors


Lecture


Conversation


Test Number




131


75


56


Test 1




139


113


26


Test 2




113


84


29


Test 3




183


148


35


Test 4




151


120


31


Test 5




 
Data Analysis of Official TOEFL iBT Tests Volume 2
Official TOEFL iBT Tests Volume 2 comprises five independent tests. As with the previous volumes, the listening section of each test includes six passages—lectures and conversations—resulting in a total of 30 listening passages analyzed for this study. The results of the clause-level analysis—including the frequency and distribution of verbal and adjectival nominalizations—are summarized in Table 5.
 
Table 5: Total Frequency of Types of Grammatical Metaphors of Nominalization in Official TOEFL iBT Tests Volume 2




Total Frequency of Metaphors


Adjectival Nominalization


Verbal Nominalization


Official TOEFL iBT Tests Volume 2




110


0


110


Conversations




575


52


523


Lectures




685


52


633


Total Frequency




As previously noted, the frequency of grammatical metaphors—particularly those involving nominalization—is consistently higher in lecture texts than in conversational ones. This trend aligns with expectations based on systemic functional linguistic theory. Table 6 presents a comparative summary of the data obtained from the five tests included in this volume.
 
Table 6: Frequency of Grammatical Metaphors of Nominalization in the Listening Sections of Official TOEFL iBT Tests Volume 2




Total Frequency of Metaphors


Conversation


Lecture


Test Number




152


128


24


Test 1




98


84


14


Test 2




158


128


30


Test 3




139


121


18


Test 4




138


114


24


Test 5




 
Discussion and Summary of Data across the Three Books
Due to the extensive dataset—over 1,900 clauses identified and analyzed as containing metaphorical meanings—only representative examples are included in this section. Tables 7 and 8 provide illustrative instances of the two major types of nominalization-based grammatical metaphor analyzed in this study.
 
Table 7: Metaphorical clause involving Verbal Nominalization (Source: Findings of the Present Study)




No.


Metaphorical (Non-congruent) Clause from Listening Section


Congruent (Literal) Clause Proposed by the Authors




1


Plato says, the third group you need is leaders.


Plato says, the third group you need is people who can lead.




2


It would be better to remove restrictions on imports and …


It would be better to remove what restricts imports and …




3


Basically, the argument is that for baleen whales, migration is a kind of balancing act.


Basically, the case that we argue about is that for baleen whales, the time they migrate is a kind of state in which they balance their acts.




 
The clause is regarded as the central processing unit of the lexico-grammar stratum (Halliday & Matthiessen, 2014:10). Accordingly, in the present study, Clause is adopted as the primary unit of analysis, considering all of its constituent elements. As illustrated in Table 7, nominal groups such as leaders, restrictions, argument, migration, and balancing have been identified within their respective clauses. These items were formed through nominalization, where specific derivational suffixes (e.g., -er, -ment, -tion, and -ing) are added to base forms, resulting in noun phrases that serve as participants within the clause structure. The derivational processes involving -ing and -er are categorized as gerundive and agentive nominalization, respectively. For instance, in Example 1, the word leader functions as a nominal group within the clause. It’s expected, congruent (i.e., literal) form would be the verbal process lead. The addition of the -er suffix shifts the word class from verb to noun, altering its grammatical role in the clause and transforming the clause from a process-based structure to a participant-based one. In Example 3, the comparison between congruent and incongruent versions highlights how grammatical metaphor affects the clause structure. The metaphorical clause—"Basically, the argument is that for baleen whales, migration is a kind of balancing act."—utilizes nominalized processes (argument, migration, balancing) as participants, with a relational process (is) expressing the experiential meaning. In contrast, the congruent version—"Basically, the case that we argue about it is that for baleen whales, the time they migrate is a kind of state in which they balance their acts."—realizes the material processes argue, migrate, and balance explicitly as verbs, resulting in a longer and more elaborated clause structure.
 
Table 8: Metaphorical clause involving Adjective Nominalization (Source: Findings of the Present Study)




No.


Metaphorical (Incongruent) Clause from Listening Section


Congruent (Literal) Clause Proposed by the Authors




4


If we're going to discuss goodness and justice...


If we're going to discuss what makes an individual good and...




5


He accomplished this by giving the stage a greater feeling of depth...


He accomplished this so that he gave the stage a sense of deep perspective so that people could more greatly feel it.




6


Since the capacity for recall has always been linked with the ability to talk.


Since the power which is capable for recall has always been linked with the ability to talk.




 
As illustrated in Table 8, the selected clauses demonstrate instances where adjectives are no longer realized as qualities, but rather as things—that is, they are expressed as nominal groups within the lexicogrammar stratum. This shift reflects a key feature of adjectival nominalization, a type of experiential grammatical metaphor. In Example 4, the embedded clause “If we're going to discuss what makes an individual good…” represents the congruent (i.e., literal) realization of the adjective good. However, in the metaphorical version of the clause, this quality is condensed into the noun goodness. Such a transformation is particularly characteristic of formal or academic discourse, where lexical density and semantic abstraction are prioritized. The nominalization of good into goodness reflects a structural shift at the lexicogrammar level, resulting in a more compact and abstract expression of meaning. This is a hallmark of grammatical metaphor within the Systemic Functional Linguistics (SFL) framework. As previously mentioned, this study focuses specifically on grammatical metaphors found in materials officially endorsed by the TOEFL test’s administering organization, within a standardized academic context. In Examples 5 and 6, similar metaphorical transformations are observed: depth and capacity are used in place of their congruent adjectival counterparts, deep and capable, respectively. These nominalizations involve a shift in word class (from adjective to noun), leading to corresponding changes in syntactic roles and clause structure. Such transformations are not merely stylistic, but rather serve important functional purposes: they increase abstraction, facilitate meaning condensation, and enable the reorganization of information in a way that aligns with the communicative demands of academic discourse. Consequently, these examples exemplify the incongruent and metaphorical nature of adjectival nominalization in TOEFL listening texts. Taking into account the analyses presented above, a total of 14 TOEFL tests were examined across the three selected books. Each test includes six listening passages—comprising both conversations and lectures. In total, 1,906 grammatical metaphors involving nominalization were identified and systematically analyzed. A comparative analysis of the data from all tests revealed that there is no statistically significant difference in the overall frequency of nominalization-based grammatical metaphors among the three books. However, a consistent pattern emerged: the lecture sections contained a substantially higher number of grammatical metaphors than the conversation sections. Specifically, approximately 79% of all identified nominalizations occurred in the lecture texts, indicating a strong correlation between register and the distribution of grammatical metaphors. Table 9 below presents the total frequency distribution of nominalization-based grammatical metaphors across the two listening text types—conversations and lectures—in all 14 TOEFL tests analyzed in this study.
 
Table 9: Total Frequency of Nominalization Metaphors in the Listening Sections of the Three Books (Source: Findings of the Present Study)




Book


Lecture


Conversation


Total Nominalizations




Official Guide to the TOEFL iBT
(includes 4 tests)


387


117


504




Official TOEFL iBT Tests Volume 1 (including 5 tests)


540


177


717




Official TOEFL iBT Tests Volume 2 (including 5 tests)


575


110


685




Total


1502


404


1906




As follows, figure 1 illustrates the distribution of frequencies for the two types of grammatical metaphors—verbal nominalization and adjectival nominalization—within the three TOEFL test preparation books analyzed in the present study.
 
 
Fig 1: Frequency Distribution of Types of Nominalizations as Grammatical Metaphors in three Official TOEFL iBT Books
 
As shown in Figure 1, a total of 1,906 clauses exhibiting grammatical metaphor through nominalization were identified and analyzed across 84 listening texts (comprising both lectures and conversations) drawn from the listening sections of three benchmark TOEFL preparation books. Of these, only 153 instances (8%) were adjectival nominalizations, while the remaining 1,753 clauses (92%) involved verbal nominalizations.
 
Conclusion
The present study described and analyzed nominalization as Grammatical Metaphors in the listening module of the TOEFL official text books, using Systemic Functional Grammar (Halliday & Matthiessen, 2014). The data were collected through documentary (library) method research, and examined using a qualitative content analysis. In this regard, the listening modules of three textbooks (containing fourteen tests in conversations and lectures formats) were selected. In the next step, the clauses of 84 texts were analyzed. First, clause by clause of these texts was separately examined. Then, nominalizations as Grammatical Metaphors were compared and analyzed in terms of type and frequency. The main findings are summarized below: 1) In Official Guide to the TOEFL iBT Test, a total of 504 verbal nominalization metaphors were identified. Of these, 23% occurred in conversation texts and 77% in lecture texts. Verbal nominalizations accounted for 91% of the total, while adjectival nominalizations comprised only 9%. 2) In TOEFL iBT Practice Tests Volume 1, 717 nominalization metaphors were found—25% in conversations and 75% in lectures. Verbal nominalizations made up 92%, and adjectival nominalizations 8%. 3) In TOEFL iBT Practice Tests Volume 2, 685 nominalization metaphors were identified. Of these, 16% appeared in conversation texts and 84% in lecture texts. Again, verbal nominalizations constituted 92%, and adjectival ones 8%. The results indicated that: 1. A total of 1,906 Grammatical Metaphors of nominalization were identified. There was a higher frequency of nominalization in lecture texts (79%) than the texts of conversations (21%). 2. De-verbal nominalization had a frequency of 1753 cases equal to 92%, and only 8% of the total frequency were found for de-adjectival nominalization. The findings showed that the officially recognized TOEFL textbooks employ both de-verbal and de-adjectival metaphors in the conversations and lectures texts of the listening module. The higher frequency of nominalization in lecture texts aligns with the structural features of scientific and academic language. Since Grammatical Metaphor is one of the most important characteristics of academic, and scientific discourses, and Nominalization is a powerful resource in recognizing Grammatical Metaphors and is a determining factor in the complexity of texts with more lexical density, prioritizing lecture texts in TOEFL listening modules could enhance their effectiveness in measuring the communicative and metaphorical competence of the language learners.
 
References

Afshar, M., Gorjian, B., Veysi, A., Sharafi, S., & Shekaramiz, M. (2020). “The Candidates' Inferring Problems of TOEFL Listening Module”. Journal of Linguistics, 12(37), 267–295. [In Persian]
Bachman, L.F. & Palmer, A.S. (1996). Language Testing in Practice: Designing and Developing Useful Language Tests. Oxford: OUP.
Banks, D. (2005). “On the historical origin of nominalized process in scientific text”. English for Specific Purposes. 24, 347-357.
Banks, D. (2011). “The evolution of grammatical metaphor in scientific writing”. In Grammatical metaphor: Views from systemic functional linguistics(pp. 127-147). John Benjamins Publishing Company.
Bhatia, V. K. (1993). Analyzing genre, Language use in professional settings. Applied Linguistics and Language Study. London: Longman.
Biber, D. (1988). Variation across speech and writing. Cambridge University Press.
Biber, D. (2006). University language: A corpus-based study of spoken and written registers. viii, 261 pp. John Benjamins Publishing Company
Biber, D., & Gray, B. (2021). “Nominalizing the verb phrase in academic science writing”. In The register-functional approach to grammatical complexity(pp. 176-198). Routledge.
Bloor, T., & Bloor, M. (1995). The functional analysis of English: A Hallidayan approach. London: Arnold.
Bloor, T., & Bloor, M. (2013). The functional analysis of English: A Hallidayan approach. Routledge.
Bonelli, E. T. (2008). “Corpora and LSP: Issues and implications”. Corpora for University Language Teachers. Edited by Carol Taylor Torsello, Katherine Ackerley and Erik Castello. Bern: Peter Lang CH, 31-48.
Canale, M. and Swain, M. (1980). “Theoretical bases of communicative approaches to second language teaching and testing”. Applied Linguistics 1 (1), 1-47.
Charles, M. (2003). “This mystery…’: a corpus-based study of the use of nouns to construct stance in theses from two contrasting disciplines”. Journal of English for Academic Purposes, 2(4), 313-326.
Chavooshi, M. (2011). The Use of Grammatical Metaphor in Language of Science. Master’s thesis, Allameh Tabataba’i University, Tehran, Iran). [In Persian]
Christie, F., & Martin, J. R. (1997). Genre and institutions: Social processes in the workplace and school. London: Cassell.
Dabir-moghaddam, M. (2008). Theoretical Linguistics: Emergence and Development of Generative Grammar (3rd ed). Tehran: SAMT Publications. [In Persian]
Dabir-moghaddam, M. (2016). Theoretical Linguistics: Emergence and Development of Generative Grammar (3rd ed). Tehran: SAMT Publications. [In Persian]
Devrim, D. Y. (2015). “Grammatical Metaphor: What do we mean? What exactly are we researching?” Functional Linguistics, 2(1), 3.
Educational Testing Service. (2016). Official TOEFL iBT Tests. Vol.2, (3rd ed). McGraw Hill Professional.
Educational Testing Service. (2017). The official guide to the TOEFL test. (5th ed). McGraw Hill Professional.
Educational Testing Service. (2018). Official TOEFL iBT Tests. Vol.1, (3rd ed). McGraw Hill Professional.
Eggins, S. (1994). Introduction to systemic functional linguistics. (1st ed). Pinter, London.
Gebhard, M., Chen, I. A., & Britton, L. (2014). “Miss, nominalization is a nominalization”, English language learners’ use of SFL metalanguage and their literacy practices. Linguistics and Education, 26, 106-125.
Halliday, M. A. K. (1985/1994/1998). An Introduction to Functional Grammar. London: Edward Arnold Limited.
Halliday, M. A. K. (1988). “On the language of physical science”. Registers of written English: Situational factors and linguistic features, 162-178.
Halliday, M. A. K. (1989). Spoken and written language. Oxford University Press, USA.
Halliday, M. A. K. (2004). Language of science. Continuum, London.
Halliday, M. A. K., & Matthiessen, C.M.I.M. (1999). Construing experience through meaning: A language-based approach to cognition. A&C Black.
Halliday, M.A.K & Martin J. (1993). Writing Science: Literacy and Discursive Power. University of Pittsburgh Press, Pittsburgh.
Halliday, M.A.K., & Matthiessen, C.M.I.M. (2014). Halliday's Introduction to Functional Grammar (4th ed.). Routledge.
Heyvaert, L. (2011). “Nominalization as grammatical metaphor: On the need for a radically systemic and meta-functional approach”. In Grammatical metaphor: Views from systemic functional linguistics(pp. 65-99). John Benjamins Publishing Company.
Holtz, M. (2009). “Nominalization in scientific discourse: a corpus-based study of abstracts and research articles”. In Proceedings of the Corpus Linguistics Conference 2009 (CL2009), (p. 341).
Hyland, K. (2004). Genre and second language writing. University of Michigan Press.
Hyland, K. (2008). “Academic clusters: Text patterning in published and postgraduate writing”. International journal of applied linguistics, 18(1), 41-62.
Hyland, K. (2009). Academic discourse: English in a global context. London: Continuum.
Jalilifar, A., Alipour, M., & Parsa, S. (2014). “Comparative Study of Nominalization in Applied Linguistics and Biology Books”. Research in Applied Linguistics, 5, 24-43.
Jodairi Pineh, A. (2022). “Exploring Nominalization Use in EFL Students’ Argumentative Writing over a Genre-Based Teaching and Learning Approach”. Journal of Research in Applied Linguistics,13(1), 110-122.
Kazemian, B., Behnam, B., & Ghafoori, N. (2013). Ideational Grammatical Metaphor in Scientific Texts: A Hallidayan Perspective. International Journal of Linguistics, 5, 146-168.
Lees, R. B. (1962). “The grammar of English nominalizations”. Journal of Symbolic Logic, 27(2).
Liardet, C. L. (2013). A corpus-assisted study of Chinese EFL learners' development of academic literacy. Doctoral Thesis. Macquarie Sydney.
Liardet, C. L. (2014). “A'speedful development': academic literacy in Chinese learners of English as a foreign language”. In Corpus analysis for descriptive and pedagogical purposes(pp. 303-324). Peter Lang.
Liardet, C. L. (2015). “Academic literacy and grammatical metaphor: Mapping development”. TESOL International Journal, 10(1), 29-46.
Liardet, C.L. (2016). "Nominalization and grammatical metaphor: Elaborating the theory”. English for Specific Purposes. 44, 16-29.
Mahbudi, A., Mahbudi, L., & Amalsaleh, E. (2014). “A Comparison between the Use of Nominalization in Medical Papers by English and Iranian Writers”. International Journal of Applied Linguistics and English Literature, 3, 1-6.
Mahfudurido, I., Tallapessy, A., & Kusumayanti, D. D. (2021). “Exploring Nominalization Use in Graduate Thesis Abstracts: An SFL Approach to Academic Writing”. Leksema: Journal Bahasa dan Sastra, 6(2), 125-139.
Martin, J. R. (1992(. English text: System and structure. Amsterdam: John Benjamins.
Martin, J. R. (2008). “Incongruent and proud: de-vilifying 'nominalization'.” Discourse & Society, 19(6), 801-810.
Matthiessen, C. M. I. M. (1995). Lexico-grammatical Cartography: English Systems. International Language Sciences Publisher.
Mirzaei Hesarian, M., & Ahmadi, S. (2020). “Grammatical Metaphor from the Perspective of Persian Language Teaching and Learning: An Analysis Based on the Language Perspective of the Halliday Foundation”. Journal of Persian Language International Teaching Studies, 6(6), 11–38. [In Persian]
Mobaraki, S. (2012). Grammatical Metaphor in Scientific and Literary Texts. (Master’s thesis, Semnan University, Semnan, Iran). [In Persian]
Nunan, D. & Miller, L. ed. (1995). New ways in teaching listening. TESOL Inc.
Ravelli, L. J. (1988). “Grammatical metaphor: An initial analysis. Pragmatics”, discourse and text: Some systemically-oriented approaches, 133-147.
Ravelli, L. J. (1999). Metaphor, mode, and complexity: An exploration of covarying patterns. B.A. Honours thesis, University of Sydney, Department of English and Media Studies.
Rezapour, E., & Ahmadi, S. (2016). “Critical Analysis of Grammatical Metaphor of Nominalization in English and Persian Political Discourses”. Journal of language Science, 4(6), 59–82. [In Persian]
Sahraei, R. M., & Yeganeh, S. (2019). “A Comparative Study of Grammatical Metaphor in Persian Research Articles Written over the Past Three Decades”. Namaeh Farhangistan, 17(4), 113–136. [In Persian]
Simon-Vandenbergen, A. M., Ravelli, L. J., & Taverniers, M. (2003). Grammatical metaphor. Amsterdam: Benjamins, 1-460.
Swann, J., Hunston, S., & Oakey, D. (2010). Introducing applied linguistics: Concepts and skill Routledge, New York.
Taverniers, M (2006). “Grammatical metaphor and lexical metaphor: Different perspectives on semantic variation”. Neophilologus, 90(2), 321-332.
Taverniers, M. (2003). “Grammatical metaphor in SFL: A historiography of the introduction and initial study of the term”, in: Simon-Vandenbergen, Taverniers & Ravelli (eds.) Grammatical Metaphor: Views from systemic functional linguistics. (Current Issues in Linguistic Theory, 236.), Amsterdam: Benjamins, 5-33.
Thomason, G. (1996). Introducing Functional Grammar. London: Edward Arnold.
Thompson, G (2009). “Grammatical metaphor and success in academic writing”. Introducing applied linguistics: Concepts and skills, 65-99.
Wang, X (2011). Grammatical Concepts and their Application in Foreign Language Teaching, University of Tasmania. Retrieved November, 19, 335-364.
Yang, B. (2020). “Full realization principle for the identification of ideational grammatical metaphor: nominalization as example”. Journal of World Languages, 6, 161 - 174.