Who is riding on the skateboard?
The man is riding on a skateboard.
    src        edge_attr  dst
0     2  to the right of   18
1     3  to the right of    8
2     3  to the right of   15
3     3  to the right of   11
4     3  standing behind    4
5     3  to the right of   16
6     3  to the right of   13
7     5        on top of    7
8     6   to the left of   15
9     6   to the left of   16
10    6  to the right of   18
11    8   to the left of    3
12   11   to the left of    3
13   12  to the right of   18
14   12        on top of    2
15   13        riding on    2
16   13   to the left of    3
17   13  to the right of   18
18   13          wearing   15
19   13        on top of    2
20   15  to the right of    6
21   15   to the left of    3
22   16  to the right of    6
23   16   to the left of    3
24   18  standing behind    9
25   18   to the left of    2
26   18   to the left of    6
27   18   to the left of   13
28   18   to the left of   12