code: def cvc(self, i):
          
          if (
              i < (self.k0 + 2)
              or not self.cons(i)
              or self.cons(i - 1)
              or not self.cons(i - 2)
          ):
              return 0
          ch = self.b[i]
          if ch == "w" or ch == "x" or ch == "y":
              return 0
          return 1
docs: cvc(i) is TRUE <=> i-2,i-1,i has the form consonant - vowel - consonant
          and also if the second c is not w,x or y. this is used when trying to
          restore an e at the end of a short  e.g.
  
             cav(e), lov(e), hop(e), crim(e), but
             snow, box, tray.