More specifically, {HEAD ~ the invention} relates to {TAIL ~ concrete masonry blocks} which are useful in forming various retaining structures 
relates to
More specifically , { HEAD ~ the invention } relates to { TAIL ~ concrete masonry blocks } which are useful in forming various retaining structures
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH