The_Complete_Idiot%27s_Guide_To_Music_Theory

Mary Had a Little Lamb
Finally, let’s figure out the chords to “Mary Had a Little Lamb.” Just as the melody
is a simple one, so is the accompanying chord progression—nothing more than
I-V-I, repeated once. Sometimes the simplest progressions are the best!
The chords to “Mary Had a Little Lamb.”
Chord Writing Tips
When it comes to fitting a chord progression to an existing melody, here are
some tips to keep in mind:
◆ Try some common chord changes first. You’d be surprised how many
melodies fit with the I-IV-V progression!
◆ The main notes in the melody (typically the notes that fall on the first and
third beats of a measure) are the first, third, or fifth note of the underlying
chord.
◆ Try to simplify the melody by cutting out the passing and neighboring
tones (typically the shorter notes, or the notes not on major beats); the
main notes you have left often will suggest the underlying chord.
◆ Make sure you’re in the right key. In most cases, the “home” note in the
melody is the tonic note of the underlying key.
◆ Generally, the slower the tempo, the more frequent the chord changes.
(So if you have a long whole note, or a note held over several measures,
expect to find several different chords played behind that single note.)
◆ Work backward from the end of a melodic phrase, remembering that
melodies almost always end on the I chord. You then can figure out the
cadence leading to the I, and have half the song decoded fairly quickly.
◆ Chord changes generally fit within the measure structure, which means
you’re likely to see new chords introduced on either the first or third beat
of a measure.
Chapter 10: Chord Progressions
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