{TAIL ~ Such hydroxyl groups} may be formed on {HEAD ~ the surfaces} of both organic and inorganic materials 
{ TAIL ~ Such hydroxyl groups } may be formed on { HEAD ~ the surfaces } of both organic and inorganic materials
TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH