procedure tpick (file_name, n, x)

string file_name {prompt="Input file containing a stream of words"}
real n {prompt="Pick off every nth entry"}
real x {prompt="Starting from x"}
struct *flist

begin

	string nthWORD
	struct currentWORD
	real j			# counter
	real Y
	real Yint

	flist = file_name

	j = 0.

	while (fscan (flist, currentWORD) != EOF) {

		j=j+1.
		Y=((j-x)/n)
		Yint=(real(int(Y)))
		# condition for inclusion is that int(Y)==Y

		if (Yint==Y) {
			nthWORD=currentWORD
			print (nthWORD)
		}


	}

end