a length of roving, comprising {TAIL ~ a bundle} of {HEAD ~ flexible filaments} and including: 
a length of roving , comprising { TAIL ~ a bundle } of { HEAD ~ flexible filaments } and including :
OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH