{HEAD ~ The fiber aggregates} are useful, for example, for {TAIL ~ flowback control} in wellbores and reservoirs 
{ HEAD ~ The fiber aggregates } are useful , for example , for { TAIL ~ flowback control } in wellbores and reservoirs
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH