{TAIL ~ Thus, any occurrence} of a combination of sequences that causes large interference may reduce {HEAD ~ the communications quality} 
{ TAIL ~ Thus , any occurrence } of a combination of sequences that causes large interference may reduce { HEAD ~ the communications quality }
TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD