static L<SS> speechLogToLine1AndLine2Superposition(LS log) {
  ret pairsToTwoElementCIMaps_lazy("line 1", "line 2",
  overlappingPairs_lazy(log));
}

static L<SS> speechLogToLine1AndLine2Superposition() {
  ret speechLogToLine1AndLine2Superposition(speechLog());
}