Write a line against a fixed cantus firmus, using only consonances (or carefully handled dissonances) and smooth, independent motion — Fux's method, species by species. First is note-against-note; second and third add two then four notes per bar (passing and neighbor dissonances off the beat); fourth syncopates into suspensions that resolve down by step; fifth is florid — a free mix. The counterpoint can sit above or below the cantus firmus. Move each note with the arrows; every beat's interval is shown and the line is graded live.