Individual lines are more easily read by recognizing the types and direction of motion involved. No motion consists of held notes or repeats. Step motion consists of moving up or down by the interval of a second. Small leaps are thirds and fourths, and large leaps are anything larger. Most melodies move by small steps, rather than by leaps.
Large leaps are rare, even in instrumental music.
When leaps occur they are usually chord arpeggiations. So, leaping motion should be recognized as part of a specific chord, which relies on familiarity of chords. Ex 1 Ex 1 is from Offenbach's La Perichole. A partial analysis is shown. The phrase marks show the beginnings and endings of the phrasing.