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  • BA in English Studies (First Class Honours), The University of Hong Kong
  • PGDE in English Language Teaching, The Chinese University of Hong Kong
  • MSc in Applied Linguistics and Second Language Acquisition (Distinction), University of Oxford
  • EdD in English Language Education, The University of Hong Kong

Juan has been teaching English at tertiary level since 2005.  At HKU, he mainly teaches academic literacy courses at undergraduate level, especially medicine related ones.  He also assists in the running of the Writing Centre.  Externally, he serves as an examiner for the Hong Kong Examinations and Assessment Authority regularly.

His academic interests include vocabulary acquisition, the effects of formulaic sequences on perceived L2 speaking proficiency and the issue of modality in vocabulary measurement.  His doctoral thesis is entitled “Modality and the Nature of Speaking Task as Mediators of the Effects of Collocation Knowledge on Perceived Speaking Proficiency in English as a Second Language”.  He will be supervising dissertations/portfolios in 2021-22 for the Centre’s MAAL/MATESOL programmes.

In-House Committees:

Masters Committee,Teaching and Learning

Other Major Administrative Roles:

  • Deputy Coordinator, Writing Centre, HKU
  • Timetabling Officer, CAES, HKU

Selected Publications / Presentations:

  • Cheung, M.L., & Castillo, J.T. (June 2014). What is possible with corpus-based learning? Integration of Moodle with dentistry corpora in the English-in-the-Discipline course. Paper presented at The CITE Research Symposium 2014. The University of Hong Kong, Hong Kong.
  • Murphy, V.A., & Castillo, J.T. (2013). Modality, Vocabulary Size and Question Type as Mediators of Listening Comprehension Skill. Contemporary Foreign Languages Studies, 396(12), 15-30.


Office: Room 6.04

Telephone: 3917 7250

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