▁may ▁also ▁be ▁a ▁full ▁performance ▁track ▁for ▁more ▁than ▁one ▁vo icing . ▁ ▁An ▁" ac comp an iment ▁only " ▁track ▁that ▁includes ▁only ▁the ▁instrument al ▁version ▁of ▁the ▁arrangement . ▁( Or ▁side ▁B ) ▁ ▁In ▁addition , ▁some ▁CD s ▁include ▁more ▁" Tra x " ▁that ▁start ▁the ▁song ▁at ▁a ▁certain ▁measure ▁of ▁the ▁arrangement ▁for ▁both ▁the ▁full ▁performance ▁and ▁the ▁accompan iment . ▁These ▁" Tra x " ▁are ▁generally ▁only ▁used ▁for ▁re he ars al ▁purposes . ▁ ▁Some ▁older ▁Show Tra x ▁c ass ettes ▁have ▁a ▁spoken ▁introduction . ▁The ▁introduction ▁usually ▁consists ▁of ▁a ▁brief ▁description ▁about ▁the ▁song ▁as ▁well ▁as ▁an ▁advert is ement ▁" pl ug " ▁for ▁an ▁introduction ▁about ▁the ▁song . ▁Sometimes , ▁it ▁has ▁a ▁brief ▁history ▁or ▁origin ▁of ▁the ▁song . ▁However ▁at ▁the ▁end ▁it ▁will ▁always ▁say , ▁" Here ▁is ▁S ONG " ▁and ▁then ▁the ▁song ▁will ▁begin . ▁ ▁Here ▁are ▁three ▁examples ▁of ▁a ▁Show Tra x ▁introduction : ▁ ▁" This ▁Kir by ▁Shaw ▁classic ▁capt ures ▁all ▁the ▁special ▁charm ▁of ▁the ▁great ▁hol iday ▁season ▁and ▁is ▁good ▁swing in ' ▁fun ▁all ▁the ▁way . ▁Here ▁is ▁' Let ▁it ▁Snow , ▁Let ▁it ▁Snow , ▁Let ▁it ▁Snow .' " ▁ ▁" Don ' t ▁miss ▁this ▁powerful ▁Kir by ▁Shaw ▁classic ▁rock ▁arrangement ▁of ▁the ▁eight ies ▁m ega - hit ... Fl ash d ance