# File lib/linguistics/en.rb, line 1713
    def separate!( value=:__no_arg__ )
        raise ArgumentError, "wrong number of arguments: (0 for 1)" if
            value == :__no_arg__ && !block_given?

        (1..( (self.length * 2) - 2 )).step(2) do |i|
            if block_given?
                self.insert( i, yield(self[i-1,2]) )
            else
                self.insert( i, value )
            end
        end
        self
    end