#!/bin/bash
find . -name '*.txt' |
  awk '
  {	path = $0
	for(i in line)
		delete line[i]
	mlc = lc = 0
  	while((rc = (getline < path)) == 1) {
		if(!NF)	continue
		else if($0 == "CONTINUE")
			lc = 0
		else if($0 == "DONE") {
			close(path)
			if(mlc) {
				for(i = 1; i <= mlc; i++)
					print line[i] > path
				printf("%d line table placed in \"%s\".\n", mlc,
				    path)
			} else	printf("No data found in \"%s\".\n", path)
			break
		} else {if(++lc > mlc)
				mlc = lc
			line[lc] = ((line[lc] != "") ? line[lc] " " : "") $0
		}
	}
	if(rc == 0)
		printf("Previously converted \"%s\"?  DONE not found.\n", path)
	else if(rc == -1)
		printf("Error while reading \"%s\"!  No changes made.\n", path)
	close(path)
  }'

3 line table placed in "./1.txt".
4 line table placed in "./2.txt".
4 line table placed in "./3.txt".

ages-eligible-for-study: 18-months-to-36-months
genders-eligible-for-study: both
accepts-healthy-volunteers: yes

non-electric-grass-pitch 10-x
electric-grass-pitch 10-x
towan-two-bedroom-holiday-home 6-x
crantock-two-bedroom-apartment 4-x

size alt axlt a2xlt a3xlt
waist-(on-half) 14" 15" 16" 17"
hip-(on-half) 24-3/4" 26-3/4" 28-3/4" 30-3/4"
inseam 34" 34-1/2" 35" 35-1/2"