private String spaceSet(Set set) {
		Iterator it = set.iterator();
		boolean first = true;
		StringBuffer sb = new StringBuffer();
		while (it.hasNext()) {
			if (!first)
				sb.append(" ");
			String s = (String) it.next();
			sb.append(s.equals("") ? "!" : s);
			first = false;
		}
		return sb.toString();
	}