When the lid is in the first position it covers {HEAD ~ substantially all} of {TAIL ~ the top opening} of the container 
of
When the lid is in the first position it covers { HEAD ~ substantially all } of { TAIL ~ the top opening } of the container
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH