那首老歌触动了他的心弦。
The old song struck a ___chord in his heart.
钢琴老师教我如何弹奏C大调的和弦。
The piano teacher showed me how to play the C major ___chords.
这首歌的歌词在我们心中引起了强烈的共鸣。
The lyrics of this song struck a powerful ___chord in our hearts.