The lower portion is recessed relative to the upper portion in {HEAD ~ a direction} toward {TAIL ~ the opposite cutting edge} 
toward
The lower portion is recessed relative to the upper portion in { HEAD ~ a direction } toward { TAIL ~ the opposite cutting edge }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL