The jat-reflex rules are not without exception. For example, when short jat is preceded by r, in most Ijekavian dialects developed into /re/ or, occasionally, /ri/. The prefix prě- ("trans-, over-") when long became pre- in eastern Ijekavian dialects but to prije- in western dialects; in Ikavian pronunciation, it also evolved into pre- or prije- due to potential ambiguity with pri- ("approach, come close to"). For verbs that had -ěti in their infinitive, the past participle ending -ěl evolved into -io in Ijekavian Neoštokavian.
To what did the ending -ei evolve into in Ijekavian Neostokavian? What is the western equivalent of the prefix "pre"? Why did pre or prije develop rather than the symboled "pre"? What is the meaning of "pri"?