1 | BBC (2003). Better speaking: A guide to improving your spoken English. British Broadcasting Cooperation. |
2 | Biber, D., Conrad, S., & Leech, G. (2002). Longman student grammar of spoken and written English. Harlow: Longman. |
3 | Brown, H. D. (2015). Teaching by Principles: An Interactive Approach to Language Pedagogy (4th ed.). Pearson Education. |
4 | Celce-Murcia, M., Brinton, D. M., & Snow, M. A. (2014). Teaching English as a Second or Foreign Language (4th ed.). National Geographic Learning. |
5 | Thornbury, S. (2005). How to Teach Speaking. Pearson Education. |