The teacher rolled the gumball on the box .
* teacher ( x _ 1 ) ; * gumball ( x _ 4 ) ; * box ( x _ 7 ) ; roll . agent ( x _ 2 , x _ 1 ) AND roll . theme ( x _ 2 , x _ 4 ) AND gumball . nmod . on ( x _ 4 , x _ 7 )