Therefore, even if {HEAD ~ a main course box} is out of {TAIL ~ order} the data remains in the sub course box 
Therefore , even if { HEAD ~ a main course box } is out of { TAIL ~ order } the data remains in the sub course box
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH