{HEAD ~ The single crystal blades} are provided with {TAIL ~ a root portion} which contains a recess or cavity which conforms closely to the disk protrusion 
are provided with
{ HEAD ~ The single crystal blades } are provided with { TAIL ~ a root portion } which contains a recess or cavity which conforms closely to the disk protrusion
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH