Formally the word 'yes' in English is translated into 'ya' in Indonesian. However this short answer 'ya' sounds like 'eeyah' when the speaker says it more slowly, so rather than saying the short 'ya', the speaker says it 'iya' which sounds like 'eeyah'.
In many informal situation such as in comic books, the word 'iya' (which sounds like 'eeyah') instead of 'ya' is very common.
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