A bottom gate holds its frozen bait in the tunnel until {HEAD ~ the blades} have sliced {TAIL ~ the bait} into pieces 
A bottom gate holds its frozen bait in the tunnel until { HEAD ~ the blades } have sliced { TAIL ~ the bait } into pieces
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH