Rizqi Y. answered 07/13/20
Teacher for kids! I am a SpEd.Elementary Resource Teacher in Tx
Yes they are. Indonesian become more widely spoken compare to Javanese and Sundanese as these two languages are considered traditional language which only be use at its original city itself. However Indonesian language is our main national language since there will be many foreigners of Indonesian who visits Bandung from Jakarta or vice versa so if they don't know how to speak Sundanese they can always speak Bahasa Indonesia and local people would still understand. So it is better to know about Bahasa Indonesia instead of learning the traditional languages (Javanese or Sundanese), however this is also depends on your purpose of learning the language or visiting the city. Please reach out to me if you want to learn Bahasa Indonesia for conversational, business language, listening, writing or reading. I have 7 years experience in teaching Bahasa Indonesia for foreigners and children. Thank you!!