A modified version of Sodian et al.’s (1991) Experiment 2 was then administered. Compared to the original version, the procedure of the modified version reported here was simpler. Children were introduced to a doll, named Ming (a popular Cantonese name), who is going to take off his shoes (E1 took the caps off the felt-tip pens which were hidden under Ming's pants) and walk over a white board to hide a treasure (i.e., a sweet) in one of four colored opaque boxes (E1 demonstrated the action). Children were shown that Ming left a clear trail of footprints (on the white board) wherever he walked. E1 then demonstrated that the trail of footprints could be removed with an eraser “so that one cannot see where Ming had walked”. Children were asked to assist in removing footprints. E1 then made Ming walk on the board again and demonstrated that the trail of the footprints could be strengthened by drawing a parallel line with a red felt-tip pen “so that one can see better where Ming had walked”. Children were also asked to assist in drawing the line. Then everything returned to its original status and children's understanding of the association between Ming's footprints and the treasure's location were checked by asking children to search for the treasure. If children failed, E1 guided them to look where Ming had walked. The procedures were repeated until children followed the footprints to find the treasure without prompting.