The aforesaid raw material can be used as such or after diluted with {HEAD ~ water} to {TAIL ~ a desired concentration} 
to
The aforesaid raw material can be used as such or after diluted with { HEAD ~ water } to { TAIL ~ a desired concentration }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL