{
    "hints":  [
                  {
                      "text":  "Fold the figure along Line XY and compare the two sides.",
                      "level":  1
                  },
                  {
                      "text":  "If both halves match exactly, then XY is a line of symmetry.",
                      "level":  2
                  },
                  {
                      "text":  "Line XY splits the figure into two matching halves, so it is a line of symmetry.",
                      "level":  3
                  }
              ]
}