By comparing the features of personal pronoun of English and Indonesian, conclusion can be drawn that learners of English, whose native language is Indonesian, potentially encounter difficulties. Those difficulties, most of which, are (borrowing Prato’s terms, in Brown,1980) coalescence, overdifferenciation and split.
Based on the critical analysis of the two languages – English and Indonesian, especially on personal pronouns, it is suggested that teachers of English consider the findings of this research in addition to other features of the two languages that differ when designing or planning their lessons.