References
- Biber, D., Johansson S., Leech, G., Conrad, S., & Finegan, E. (1999). Longman Grammar of Spoken and Written English. Harlow: Pearson Education.
- Charlow, N., & Chrisman, M. (2016). Deontic Modality. New York, NY: Oxford University Press.
- Chen, H. (2010). Contrastive learner corpus analysis of epistemic modality and interlanguage pragmatic competence. Arizona Working Papers in SLA & Teaching, 17, 2-51.
- Chen, Z. (2012). Expressions of epistemic stance in EFL Chinese university students' writing. English Language Teaching, 5(10), 173-179.
- Coates, J. (1995). The expression of root and epistemic possibility in English. In Bybee, J., & Fleischman, S. (Eds.), Modality in Grammar and Discourse (pp. 55-66). Amsterdam: John Benjamins.
- Depraetere, I., & Reed, S. (2006). Mood and modality in English. In Aarts, B., & McMahon, A. (Eds.), The Handbook of English Linguistics (pp. 269-290). Oxford: Blackwell.
- Ellis, N. C. (2002). Frequency effect in language processing: A review with implications for theories of implicit and explicit language acquisition. Studies in Second Language Acquisition, 24(2), 143-188. https://doi.org/10.1017/S0272263102002024
- Halliday, M. (1970). Functional diversity in language as seen from a consideration of modality and mood in English. Foundations of Language, 6(3), 322-361.
- Hamp-Lyons, L., & Mathias, S. (1994). Examining expert judgments of task difficulty on essay tests. Journal of Second Language Writing, 3(1), 49-68. https://doi.org/10.1016/1060-3743(94)90005-1
- Hinkel, E. (1995). The use of modal verbs as a reflection of cultural values. TESOL Quarterly, 29(2), 325-343. https://doi.org/10.2307/3587627
- Hinkel, E. (2009). The effects of essay topics on modal verb uses in L1 and L2 academic writing. Journal of Pragmatics, 41, 667-683. https://doi.org/10.1016/j.pragma.2008.09.029
- Holmes, J. (1988). Doubt and certainty in ESL textbooks. Applied Linguistics, 9, 20-44. https://doi.org/10.1093/applin/9.1.21
- Hu, C., & Li, X. (2015). Epistemic modality in the argumentative essays of Chinese EFL Learners. English Language Teaching, 8(6), 20-31.
- Hyland, K. (1994). Hedging in academic writing and EAP textbooks. English for Specific Purposes, 13, 239-256. https://doi.org/10.1016/0889-4906(94)90004-3
- Hyland, K. (2005). Metadiscourse: Exploring Interaction in Writing. London: Continuum.
- Hyland, K., & Milton, J. (1997). Qualification and certainty in L1 and L2 students' writing. Journal of Second Language Writing, 6(2), 183-205. https://doi.org/10.1016/S1060-3743(97)90033-3
- Kiefer, F. (1994). Modality. In Asher, R. E. (Ed.), The Encyclopedia of Language and Linguistics (pp. 2515-2520). Oxford: Pergamon.
- Kim, C., & Suh, H. (2014). Epistemic rhetorical stance: Hedges and boosters in L1 and L2 students' English writing. The Linguistic Association of Korea Journal, 22(2), 61-93. https://doi.org/10.24303/lakdoi.2014.22.2.61
- Lackoff, G. (1972). Hedges: A study in meaning criteria and the logic of fuzzy concepts. Chicago Linguistic Society Papers, 8, 183-228.
- Maynard, S. (1993). Discourse Modality: Subjectivity, Emotion, and Voice in the Japanese Language. Amsterdam: John Benjamins.
- McEnery, T., & Kifle, N. (2002). Epistemic modality in argumentative essays of second-language writers. In Flowerdew, T. (Ed.), Academic Discourse (pp. 182-195). London: Longman.
- Milton, J., & Hyland, K. (1999). Assertions in students' academic essays: A comparison of L1 and L2 writers. In Berry, R., Asker, B., & Lam, M. (Eds.) Language Analysis Description, and Pedagogy (pp. 147-161). Hong Kong: HKUST.
- Oh, S. (2007). A corpus-based study of epistemic modality in Korean college students' writing in English. English Teaching, 62(2), 1-29.
- Palmer, F. R. (2001). Mood and Modality. Cambridge: Cambridge University Press.
- Portner, P. (2009). Modality. Oxford: Oxford University Press.
- Saeed, J. (2009). Semantics. Chihester: Wiley-Blackwell.
- Takimoto, M. (2015). Assertions and lexical invisibility in EFL learners' academic essays. Journal of Pragmatics, 89, 85-99. https://doi.org/10.1016/j.pragma.2015.09.009