Complex sentence: Of the nine tracks, Toni Tennille wrote five of the songs, one of which, a re-recorded version of "Gentle Stranger" (as Tennille had originally envisioned it), was originally featured on their 1975 debut album "Love Will Keep Us Together".
Split into simpler sentences: Of the nine tracks, Toni Tennille wrote five of the songs. They also re-recorded "Gentle Strange" which was originally featured on their 1975 debut album "Love Will Keep Us Together".