When the lid is in the third position {HEAD ~ substantially all} of {TAIL ~ the top opening} of the container is uncovered 
When the lid is in the third position { HEAD ~ substantially all } of { TAIL ~ the top opening } of the container is uncovered
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 OTH OTH