I have a bachelor's degree in English Education and a Master's degree in Corporate Communication. I have been teaching in quite many institutions whether for colleges or courses for almost 16 years. The colleges where I have been teaching are LaSalle College Jakarta, IBS, Universitas Tarumanegara, Universitas Moestopo, and Mercubuana. Meanwhile, the course institutions, I have ever taught are Wall Street English, EF, CST, and TEW. I have been accustomed to teaching not only kids but also adults whether in the institutions or in private. I have ever taught some foreigners who were willing to learn Bahasa as well in the private sessions.
By mingling with the Indonesians who are able to speak English.
I think 2 months would be enough for basic understanding but if they would like to understand and are able to do the conversation in the intermediate or advance level, I may say at least 6 months needed or can be a year for the intensive learning.
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