{HEAD ~ First and second grinding apparatuses} are provided at {TAIL ~ a mounting portion} of the table, opposite one another 
are provided at
{ HEAD ~ First and second grinding apparatuses } are provided at { TAIL ~ a mounting portion } of the table , opposite one another
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH