“和音的”的英语？

这孩子的手太小,按不到钢琴上八度和音的键.The child's hands are too small to stretch to an octave on the piano.我们听到传来几下钢琴和音的声音.A few chords from a piano reached our ears.你认为这首歌过于欢快是因为通篇都是大三和音的缘故 吗 ?Do you think that this song sounds too...