In a three-part series of talks for Grammy Pro, Taylor Swift is breaking down the songwriting and production mechanics that went into making 1989. Two days ago, we heard her discuss working with Max Martin and Shellback and detail the inspiration behind “Blank Space,” and now she’s given the same treatment to “Out Of The Woods” and “I Know Places,” her collaborations with Jack Antonoff of Fun./Bleachers and Ryan Tedder. For “Out Of The Woods,” Antonoff — who Swift calls “a very quirky individual” — basically sent her the finished track, and then she added lyrics and sung melodies on top and sent it back to him in a voice memo (along with some gremlin voices — “We talk in gremlin voice when we’re in the studio because we have this weird inside joke about the movie Gremlins,” Swift says). “I Know Places,” on the other hand, was one of several song ideas Swift sent to Tedder that they ended up working on in the studio together. Listen to Swift’s explanations, the demos, and the finished products over on the Grammy Pro site here.