What is on the gray road?
The bus is on the road.
    src        edge_attr  dst
0     0               on    3
1     0               by    2
2     2               by    0
3     2  to the right of    6
4     4  to the right of    8
5     4   to the left of    9
6     5  to the right of    9
7     6   to the left of    2
8     6               in    7
9     8   to the left of    9
10    8   to the left of    4
11    9  to the right of    4
12    9               on    0
13    9   to the left of    5
14    9  to the right of    8