The classifying openings permit material which is already smaller than {HEAD ~ the size} of {TAIL ~ the openings} to fall therethrough, thereby bypassing the comminution apparatus 
of
The classifying openings permit material which is already smaller than { HEAD ~ the size } of { TAIL ~ the openings } to fall therethrough , thereby bypassing the comminution apparatus
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH