The term "four-part harmony" refers to music written for four voices or for some other musical medium—four musical instruments or a single keyboard instrument, for example—where the various musical parts can give a different note for each chord of the music.
The term "four-part harmony" refers to music written for four voices or for some other musical medium—where the various musical parts can give a different note for each chord of the music. Music is a very popular medium for communication among humans.
Music IS very popular with humans. 
( z1 multi-sentence :snt ( z2 refer :ARG1 ( z3 term :mod ( z4 harmony :mod ( z5 part :quant 4 ) ) ) :ARG2 ( z6 music :ARG1-of ( z7 write :ARG3 ( z8 or :op ( z9 voice :quant 4 ) :op ( z10 medium :mod ( z11 some ) :mod ( z12 other ) :mod ( z13 musical ) :mod ( z14 other ) :location-of ( z15 possible :ARG1 ( z16 give :ARG0 ( z17 part :mod ( z18 musical ) :mod ( z19 various ) ) :ARG1 ( z20 note :ARG1-of ( z21 differ ) ) :ARG2 ( z22 chord :mod ( z23 each ) ) ) ) ) ) ) :part z22 ) ) )