The Required Reading for Entering Systemic Functional Linguistics: A Review of Systemic Functional Grammar : A First Step into the Theory

— This article introduces the book Systemic Functional Grammar: A First Step into the Theory by Christian M.I.M. Matthiessen and M.A.K. Halliday, overviewing its contents and features. This book has involved the research fields, research models, key terms, and the origin and developmental stages of Systemic Functional Linguistics, which is the required reading to enter this filed of linguistics study and is significant for beginners.


Systemic Functional Grammar: A First
Step into the Theory by Matthiessen & Halliday (2009)  Systemic functional linguistics (hereafter, SFL) has had a significant impact in China, and its influence is increasingly growing internationally. However, as compared with such schools as Transformative-Generative grammar, SFL has yet to become mainstream in developed countries (Yang 2018). Therefore, the development of SFL requires fresh blood from this filed. However, there are too many relevant specialized books with varying levels of difficulty and differing focuses, making it difficult for beginners to follow and even causing them to give up further learning. For these reasons, this book introduces the research paradigms and basic concepts of SFL, providing further reading suggestions. For example, beginners are suggested to read Bloor & Bloor (2013), Thompson (2013), and Halliday (1994) or Halliday & Matthiessen (2004;2014) in turn.

The structure and main content of the book
The book consists of a foreword, a main text, and a glossary about terms in the appendix. The main text is divided into four chapters, each of which presents a different topic and perspective. Below is a brief overview of the foreword and viewpoints of each chapter. (systemics). The authors state clearly in this part that the book is still relevant because SFL is a "holistic approach" based on the thinking of context and system, i.e. SFL provides an overview of language as a whole before delving into the details. This indicates that reviewing the book is still of significant importance. In addition, Foreword concerns several key concepts of SFL, e.g. language is social, contextual, semiotic, stratified, systemic, and functional. Besides, the distinction between language systems is not binary but a "cline". These ideas further lead to theory studies such as "contextual theory", "instantiation", and "grammatical metaphor".

The Body
The main research filed (grammar study), methods (paradigmatic system and multi-functional models), and perspectives (three-dimensional perspective) of SFL are introduced in four chapters. Chapter 1 roughly introduces "systemic grammar"; Chapter 2 builds upon this by introducing the "functional" dimension of systemic 1 The term "construe" means "construct semiotically" (Halliday 1998: 185 imperative moods, and we can explore its internal composition from three dimensions: "from below", "from around", and "from above". ( (2) From around: This perspective explores the investigated system from other systems outside of it, including but not limited to its subsystems and simultaneous systems of the same larger system. (i) Explore the subsystems. The MOOD system has two main choices, indicative and imperative, but we can explore this system through more delicate subsystems. For instance, the indicative mood has two choices, "declarative" and "interrogative" (forming a subsystem below it), and a more delicate system will share some of the previous system's features, which can reflect the system's "entry condition"while that of indicative and imperative moods are "clause", that of declarative and interrogative moods is "subject". (ii) Explore its simultaneous systems. Other simultaneous systems with the same entry conditions (such as "clause") may also appear in the system network. For example, when selecting the MOOD system, it is inevitable to choose the POLARITY system, that is, the two options of positive and negative clauses. This further forms a complex system network that can be reflected by a matrix table (see Table 1); once an instance of the junction between two systems cannot be found, these systems cannot exist. The above two research perspectives actually demonstrate the scale of "delicacy" (from general to specific) and complexity (the interconnectedness of systems). It should be noted that each of the aforementioned perspectives can be used to describe grammatical systems.
However, the "from above" perspective may be preferred, i.e. exploring grammatical systems from a semantic perspective above. The major reason is that grammar realizes semantics: language, embedded in context, is a stratified system comprising semantic, lexico-grammatical, and phonological strata with the relation of realization.
Based on this understanding, functional grammar is a meaning-oriented approach implying that grammar is a resource for creating meaning. Therefore, functional linguists naturally tend to explore systems from a semantic perspective (Halliday & Matthiessen 2014).

Chapter 2 Expanding the (dimensions of) lexicogrammatical space
This chapter provides a preliminary exploration of three metafunctions of language (one of the theoretical foundations of SFL), and applies the semantic models of metafunctions both to paradigmatic and syntagmatic dimensions (system and structure). Besides, it also discusses the organizational principles and methods of system description, namely, using the scale of "rank" (rank refers to the hierarchical order of grammatical units, such as clauses, phrases, words, and morphemes in English -a higher rank of constituent is said to constitute the lower ones) and delicacy to describe systems and functions.
There are three metafunctions: ideational (experiential and logical), interpersonal, and textual. They can be realized at different ranks. Of those systems in different ranks, this chapter mainly focuses on metafunctions at the clause rank and the grammatical systems that embody each metafunction, such as the TRANSITIVITY system embodying the experiential function and the THEME system embodying the textual function (the MOOD system embodying the interpersonal function was introduced in In Fig. 1, the vertical axis represents the rank of grammatical units, the horizontal axis represents the semantic models of metafunctions, and the spatial intersection of these two axes represents the systems in lexico-grammar (each system can further construct a network of systems). Therefore, the spaces at the clause rank in Fig. 1 refer to the MOOD, THEME, and TRANSITIVITY systems, respectively, each of which realizes a specific metafunction. The main chapter then proceeds to discuss metafunctions of the clause rank in (grammatical) system networks.
Grammar creates meaning through two highly abstract metafunctions, the interpersonal and ideational metafunctions that are related to external phenomena outside language (textual metafunction is purely linguistic).
On the one hand, the interpersonal metafunction involves the grammatical resources (primarily  Table 2.  IJELS-2023, 8(3), (ISSN: 2456-7620)  (Recipient))", where the actor may be a person or a thing, but not a "meta-thing", i.e. a fact such as a nominalized clause (that the earth moved broke the window is impossible); material processes can also be further divided as "directed", and if they are directed, they may also be "benefactive" On the other hand, the textual metafunction produces resources for helping construe interpersonal and ideational meanings. It does so by organizing real-time information as an information unit that can be exchanged between the speaker and listener mainly through the THEME system.
The THEME system establishes a local context (clause context) in the textual environment, providing a starting point for information and an anchorpoint for the addressee to understand the information. This local environment that serves as the starting point is called the Theme, and other information expressed in this environment is the Rheme.

Chapter 3 System and text
The third chapter first introduces the matrix of metafunctions-ranks and its characteristics, and then identifies the relationship between the system and text, based on which it describes two general methods and principles for system description.
The grammar of every natural language can be summarized as a metafunction-rank matrix. See Table 2 for that of English.   IJELS-2023, 8(3), (ISSN: 2456-7620) (Int. J of Eng. Lit. and Soc. Sci.)  https://dx.doi.org/10.22161/ijels.83.9 59 The above passages all describe a task of grammatics: describing grammar. The task of grammar description requires the awareness that grammar is not arbitrary, but systems of choices. However, the task of grammatics goes beyond the description of systems. It also involves combining systems with instances or texts, and the latter relationship is called instantiation.
System and text are not completely different, but rather two perspectives on the same phenomenon, much like the relationship between climate and weather: we experience a set of synoptic phenomena as instances, referred to as the weather (the "text" in meteorology); when we look at it in the long term, in order to establish and explain the underlying rules of the phenomenon, we call it climate (the "system" in meteorology). Texts only make sense when they embody the potential of the system as instances, and systems are only effective when they are instantiated in texts.
Each instance remains alive in potential, which on the one hand strengthens the system, and on the other hand challenges and changes the system. This complementary relationship between text and system is what we understand as a live language. The network representation of a systemic grammar is a way of modeling the potential in order to continuously evolve it. One aspect of this evolution is grammaticalization: the instantiation models in texts may gradually become part of the potential of grammar. When learning grammar, one can explore the cline of instantiation ( Fig. 2), i.e. one can study any aspect of the cline: text, register, or code.
Registers (contexts of situation) are functional variants of language that vary according to different contexts: formal or informal, technical or non-technical, more open or more closed. Codes (cultural contexts) are subcultural variants, the differences in text between different ages, genders, classes within a society, which are expressed through different semantic styles. Lexico-grammatical variants that arise from differences in registers and codes are "special cases", as they mostly concern relative frequency of occurrence of an item in the system, rather than the absence or presence of the item in the entire system (e.g., in some registers, the first and second person is rare, but this does not necessarily mean that one has to construct a separate grammar that does away with the PERSON system altogether).  IJELS-2023, 8(3), (ISSN: 2456-7620)  generalizations are sought for these exceptions; and this process repeats itself.
(2) System is described from three dimensions: from below, from above, and from around (cf. Chapter 1).

Chapter 4 Perspectives beyond lexicogrammar
This chapter firstly contextualizes grammar as a stratified environment. In order to make SFL more contextualized, it then relates to various grammatical theories and other schools (mainly the general Functional Grammar).
Lexico-grammar serves as a subsystem of language embedded within the context stratum, which is a set of systems that construes meanings through wordings.  IJELS-2023, 8(3), (ISSN: 2456-7620)  language construes these meanings as simultaneous systems and structures.
In conclusion, the book elaborates on the importance of grammatics with the relation between grammatics and language. The exchange of goods-&-services and information communication constitutes a dialectical relationship between physical and semiotic processes in human history. As physical systems are taken as prototypes in modern science, all systems are modeled into physical forms. In the "postmodern" information society, since we increasingly use semiotic models, we even interpret physical systems through meaning exchange. This makes grammatics the center of times, as it is not only a theory about grammar, but a theory about knowledge -in all systems, grammar is used to construe meanings (experiences) and then store knowledge. Moreover, grammatics implies using grammar to think, grammar being as a theory. Through this theory, we can apply our understanding of language to any phenomenon. However, no theory has achieved such a level. Thus, it is important to constantly develop the theory of grammar, so that it approaches more closely the interdisciplinary fields that people are concerned about.

II. BRIEF COMMENT
From its content, we can observe that this book primarily introduces the research field (grammar), research methods (paradigmatic description of system networks and organization of functional meaning models), and research perspectives (three-dimensional perspective) of SFL, involving many core concepts such as grammar, grammatics, rank, delicacy, system, structure, metafunction, realization, stratification, context (register and code), and instantiation.
This book and this article therefore contribute to increasing the interest of beginners in SFL and aiding their theoretical development.