any-extended-rafsi is a fu'ivla, a fu'ivla-rafsi, a stressed-fu'ivla-rafsi, a brivla-rafsi or a stressed-brivla-rafsi.
A fu'ivla-rafsi consists of one or more unstressed-syllables followed by a y-syllable and possibly an apostrophe, such that it starts with a permissible initial, it doesn't start with a cmavo, and it is not a y-final rafsi-string or a slinkujy.
A stressed-fu'ivla-rafsi consists of any number of unstressed-syllables (possibly none) followed by one stressed-syllable and then followed by a y-syllable, such that it starts with a permissible initial, it doesn't start with a cmavo, and it is not a y-final rafsi-string or a slinkujy.
A brivla-rafsi consists of two or more unstressed-syllables (the last one ending in an apostrophe) followed by a y and possibly an apostrophe, such that it starts with a permissible initial, it doesn't start with a cmavo, and it is not a slinkujy.
A stressed-brivla-rafsi consists of one or more unstressed-syllables followed by one stressed-syllable (ending in an apostrophe) and then followed by a y, such that it starts with a permissible initial, it doesn't start with a cmavo, and it is not a slinkujy.
A slinkujy is a consonant followed by a y-final rafsi-string
A y-final rafsi-string consists of any number of y-less-rafsi (possibly none) followed by a y-rafsi, a stressed-y-rafsi, a stressed-y-less-rafsi plus an initial-pair and a y, or just an initial-pair and a y.