In {TAIL ~ operation}, the consumer unscrews the cap from the spout, ruptures the sealing membrane 44 at {HEAD ~ the top} of the spout and pours the desired amount of liquid out of the carton 
In { TAIL ~ operation } , the consumer unscrews the cap from the spout , ruptures the sealing membrane 44 at { HEAD ~ the top } of the spout and pours the desired amount of liquid out of the carton
OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH