Enhanced Indonesian Spelling System

The Enhanced Indonesian Spelling System (Indonesian: Ejaan Yang Disempurnakan, abbreviated EYD), also called the Perfected Spelling System (PSS), was an Indonesian-language orthography that was released in 1972 to replace the Republican Spelling System (RSS, also called the Soewandi Spelling System, SSS). The aim was greater harmonization of the Indonesian and Malay-language orthographies.

Letters that have previously been included in the Republican Spelling as foreign loan letters are officially used in the EYD Spelling.

The letters "q" and "x" are still only used in scientific subjects.

Examples:

The writing of di- and ke- (affixes) can be distinguished from di and ke (prepositions), where di- and ke- is written together with the words that follow it, for example diambil, kehendak (is being taken, desire), while di and ke is written separately with the words that follow it, for example di rumah, ke pasar (at home, to the market). This is different from the former Republican Spelling, where both di- and di are written together with the words following it.

Repeated words, mostly used in plural form of words, have to be fully written with letters, so the use of number "2" as used in the Republican Spelling is no longer valid. (In informal usage, however, the practice remains common.)

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