What animal does the bent man clean?
The man cleans the elephant.
    src        edge_attr  dst
0     0          washing    7
1     0         cleaning    7
2     0               in    1
3     0   to the left of   13
4     2           behind    6
5     3          washing    7
6     3               in    1
7     5               on   11
8     7         lying in    1
9     7               by    0
10    7               by    3
11    7               in    1
12   13  to the right of    0