The total range of a line should not exceed a tenth. Intervals Acceptable melodic intervals are major and minor seconds, thirds, and sixths, and perfect fourths, fifths, and octaves. Avoid outlining triads with consecutive thirds. Variety Unbroken ascents or descents should be limited to at most five notes. Stepwise motion is generally preferred, but a few well-considered leaps are required for variety.
Endings are always at the unison or octave.
In most cases the penultimate note of the counterpoint will be the leading tone, which must be raised in minor. Intervals permitted between the counterpoint and cantus firmus are major and minor thirds, sixths, and tenths, and perfect unisons, octaves, and fifths. Fourths are not allowed as harmonic intervals. The unison may be used only at the beginning and end of an exercise. Thirds and sixths predominate in exercises, with fifths and octaves thoughtfully deployed for variety.