A.ABACADAE B.AA1A2A3A4····An C.ABCACA D.ABABABAB
A.动机 B.乐节 C.乐句 D.乐段
A.ABACA B.AA1A2A3A4····An C.ABCACA D.ABABA
A.a+b+a+c B.a+b+a1+b1 C.a+a+a+b D.a+a+b+c
