The next strongest component of the sound you hear are the harmonics, caused primarily by the different vibration modes of the string.
(the sound; hear; you) (The next strongest component of the sound; are; the harmonics, caused primarily by the different vibration modes of the string) (the harmonics; caused; primarily by the different vibration modes of the string)
the sound The next strongest component of the sound the harmonics
hear are caused
you
the harmonics, caused primarily by the different vibration modes of the string
primarily by the different vibration modes of the string