What is he serving?
The man is serving the ball.
    src        edge_attr  dst
0     0          wearing    6
1     0          holding    3
2     0          hitting    4
3     0          wearing    5
4     0          serving    4
5     0         swinging    3
6     1   to the left of    5
7     2   to the left of    3
8     3  to the right of    2
9     5  to the right of    1
10    6   to the left of    7
11    7  to the right of    6