The method 1 where said forcing step is simultaneously performed on two sets of {TAIL ~ profiles} attached to {HEAD ~ said film} 
The method 1 where said forcing step is simultaneously performed on two sets of { TAIL ~ profiles } attached to { HEAD ~ said film }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD