In this warming-up exercise each sentence is starting in unison and at the end of the sentence the voices diverge to a harmony.
The basic melody of the exercise is the following:
Next, you may sing the exercise in two voice groups, letting sopranos and tenors sing the high notes and the altos and basses the low notes (the exercise is transposed down a whole tone):
As a following step, you create triads by letting a voice group sing the thirds in the chords. In the example below the sopranos sing that part:
Optionally, you might extend the exercise by adding the seventh to the chords. One option is to let the tenors sing the seventh (in that case the altos sing the thirds and the sopranos sing the fifths). Another possibility is the let the altos sing the sevenths: