Taylor Swift's predecessors can be listed as follows:
1. Joe Jonas: After becoming popular in 2008, Taylor Swift had a brief relationship with Disney idol Joe Jonas, which lasted for about three months.
2. Lucas Till: Taylor Swift met and briefly dated Lucas Till from "X-Men" due to filming the music video for "You Belong With Me".
3. Taylor Lautner: Taylor Lautner, the "werewolf" from the Twilight series, met and fell in love with Taylor Lautner after filming the movie "Happy Valentine's Day", and their relationship lasted for several months.
Taylor Swift's predecessors are far more than these three, but according to the requirements of the problem, only the first three are listed here to comply with the format of "1, 2, 3". Taylor Swift's other exes include John Mayer, Cory Monteith, Jake Gyllenhaal, Conor Kennedy, Harry Styles, Calvin Harris, Tom Hiddleston, and Joe Alwyn, the latter of whom is Taylor Swift's latest publicly acknowledged ex and the two have been dating for over six years.
There are many predecessors of mold and mildew, but the specific number may vary depending on different statistical standards and time points. If calculated based on publicly acknowledged boyfriends, Taylor Swift has had at least nine exes, while the number of rumored boyfriends in the community is even higher.