A storage space is defined by {TAIL ~ a wall} which in its lower portion is provided with {HEAD ~ an inclined surface}, which protrudes into the storage space 
A storage space is defined by { TAIL ~ a wall } which in its lower portion is provided with { HEAD ~ an inclined surface } , which protrudes into the storage space
OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH