Complex sentence: However, the true history is quite different: there were no diphthongs in Proto-Romance; rather, there was an (reflecting Latin "ŭ" and "ō") and an (reflecting Latin "ŏ").
Split into simpler sentences: However, the true history is quite different: there were no diphthongs in Proto-Romance. There was an (reflecting Latin "ŭ" and "ō") and an (reflecting Latin "ŏ").