Johann Sebastian Bach (1685-1750) composed three parts inventions for keyboard, BWV.787-801, for educational purposes, however, all of them are full of musical charm. They are widely known in the world and have been played by a great number of pianists. Musical scores of these peaces are not easy to read when notes belonged to different parts are close together. Unlike the case of two parts inventions, it is not easy to recognize the trajectory (IOW, envelope) of each parts because of the interference. Three columns score like a score used for organ is one of solutions. It helps pianists to study music, however, is not suitable for playing. Most of pianists are used to reading two columns score. In this score, the second parts notes are colored! As can be seen, three different parts trajectories are easily recognized because of color difference. We hope this colored score help many pianists play counterpoint music with complicated notes.