Episode Title:Conjunction Junction.Episode Description:In a railyard, a train conductor (Sheldon in his series debut) shows the viewer how conjunctions work by hooking up boxcars representing words, phrases and clauses with one of three conjunction boxcars: AND (a red boxcar), BUT (a yellow tank car), and OR (a green hopper car). This episode served as inspiration for a Norfolk Southern rail television ads that took place in the early to mid 2010s.