As a result, the tension on the clasp cannot act as {HEAD ~ a force} effective to pull apart {TAIL ~ the metallic parts} 11 and 21 
effective to pull apart
As a result , the tension on the clasp can not act as { HEAD ~ a force } effective to pull apart { TAIL ~ the metallic parts } 11 and 21
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH