{HEAD ~ The printing device} includes {TAIL ~ a printing control unit} that controls the printing processing so that a line graph representing the density change characteristic of a printing result by the printing head draws a line with a gradient 
includes
{ HEAD ~ The printing device } includes { TAIL ~ a printing control unit } that controls the printing processing so that a line graph representing the density change characteristic of a printing result by the printing head draws a line with a gradient
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH