nctional approach to the study of language and provided a great deal oflearners with three meta-functions to make further explanation of human language usedin different fields.
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Chapter Two Literature review
2.1 A review on modality in different fields
Since the studies on modality all have their own research significances and focuson different areas, which may include traditional and transformational-generativegrammar approach, semantic approach, pragmatic approach and systemic functionalapproach, the heated debate on the concept and classification of modality still does notcome to an agreement to many philosophers, logician and linguists both in China andabroad.From the perspective of the origin of modality, Aristotle mainly focused on thenotion of possibility, necessity and impossibility. Though he made studies on therelations between the three notions and drew the inspiration for the later studies, theresearch itself limited to the philosophical area.From a cognitive perspective, Sweester (2002) pointed out that modality refers toa special vocabulary area displaying the synchronic ambiguity between the internal andexternal world, which extends the concept from the domain of real world to the speechacts and from the sociophysical domain to epistemic domain.In traditional and transformational-generative grammatical approach, modality isconsidered as the meaning expressed by a series of modal auxiliaries. Scholars focus onthe syntactical and lexical levels. From the former level, linguists from traditionalgrammar discuss the morphology of the modal auxiliaries in interrogative sentence,affirmative sentence and negative sentence. As to lexical level, modality is realized inmeaning, which can be proved in the categories of modality, including possibility,necessity and willingness.Radford (1988) distinguished the modal auxiliaries from verbs according to threeforms of verbs: participle form, gerund form and the third person singular form.According to Zhang Zhenbang (1997), traditional grammar mainly took modality as themodal auxiliaries. He believed they have a syntactic role. This can be better proved intheir classification of the modal auxiliaries: primary auxiliaries, modal auxiliaries andsemi-auxiliaries . Quirk et al (1985) considered modality as the expressions showed by the modalauxiliaries like can, will, shall, may, and their deformation of tenses. Quirk (1985)pointed out there are three ways to classify modals on the meaning of modality(obligation-necessity, permission-possibility and volition-prediction) and two types(intrinsic modality and extrinsic modality) to be concerned with them.Under the influence of it, scholars emphasize their studies on modal operators andauxiliary verbs to make studies on the speaker’s attitudes and viewpoints. However,traditional linguistics paid too much emphasis on the form, logic, conception and therelative issues and they neglect the real language.Linguists in semantics area initially studied the modal logic, which are dealingwith various propositions containing the semantic expressions, such as necessity,possibility, and impossibility. At the very beginning of 20th centuries, Americanlogician Lewis uses mathematical logic theory to make a systemic research to modallogic and contributes to a new development. Based on the modal logic theory, Wright(1951) classified modality into four subcategories: alethic modality, epistemic modality,deontic modality and existential modality. His contribution made significant effects onthe later studies, especially epistemic modality and deontic modality which both areinfluential in today’s research. According to Perkins (1983), based on the proposal that aproposition can be said to be true in one particular (real or imagined) world and false inanother, the studies of modality came to a new stage.Under the dichotomy of philosophy, Lyons J (1996) indicated that modality pla
