▁chant , ▁which ▁before ▁its ▁in vention ▁was ▁taught ▁as ▁an ▁or al ▁tradition ▁in ▁mon astic ▁communities . ▁Trad itional ▁songs ▁such ▁as ▁Green ▁grow ▁the ▁r ush es , ▁O ▁present ▁religious ▁l ore ▁in ▁a ▁m nem onic ▁form , ▁as ▁do ▁Western ▁Christmas ▁car ols ▁and ▁similar ▁traditional ▁songs . ▁ ▁Work ▁songs ▁frequently ▁feature ▁call ▁and ▁response ▁structures ▁and ▁are ▁designed ▁to ▁enable ▁the ▁labor ers ▁who ▁sing ▁them ▁to ▁coordinate ▁their ▁efforts ▁in ▁accord ance ▁with ▁the ▁rh yth ms ▁of ▁the ▁songs . ▁They ▁are ▁frequently , ▁but ▁not ▁invari ably , ▁composed . ▁In ▁the ▁American ▁armed ▁forces , ▁a ▁l ively ▁or al ▁tradition ▁pres erves ▁j ody ▁calls ▁(" D uck worth ▁ch ants ") ▁which ▁are ▁s ung ▁while ▁soldiers ▁are ▁on ▁the ▁march . ▁Professional ▁sail ors ▁made ▁similar ▁use ▁of ▁a ▁large ▁body ▁of ▁sea ▁sh ant ies . ▁Love ▁poetry , ▁often ▁of ▁a ▁trag ic ▁or ▁regret ful ▁nature , ▁prom in ently ▁figures ▁in ▁many ▁folk ▁trad itions . ▁Nur ser y ▁rh ym es ▁and ▁n ons ense ▁verse ▁used ▁to ▁am use ▁or ▁quiet ▁children ▁also ▁are ▁frequent ▁subjects ▁of ▁traditional ▁songs . ▁ ▁Fol k ▁song ▁transformations ▁and ▁variations ▁▁ ▁Music ▁transm itted ▁by ▁word ▁of ▁mouth ▁through ▁a ▁community , ▁in ▁time , ▁develop s ▁many ▁variants , ▁because ▁this ▁kind ▁of ▁transmission ▁cannot ▁produce ▁word - for - word ▁and ▁note - for - note ▁accuracy . ▁Indeed , ▁many ▁traditional ▁sing