3 \context Staff=one \notes\relative c'{
4 \stemUp [c8 c \translator Staff=two \stemUp c c]
7 \stemDown [c8 c \translator Staff=two \stemUp c c]
9 \stemDown [c8 c \translator Staff=one \stemDown c c]
12 \stemUp [c8 c \translator Staff=one \stemDown c c]
15 \context Staff=two \notes\relative c'{