Complex sentence: The IPA Kiel Convention, held by the International Phonetic Association in 1989 in Kiel, Germany, adopted the first major revision of the International Phonetic Alphabet in over 50 years.
Split into simpler sentences: The IPA Kiel Convention was an event maintained by the International Phonetic Association in 1989 held in Kiel, Germany. It was the first major revision of the International Phonetic Alphabet made in over 50 years.