Olivia thought that a girl mailed the boy the potato in a room .
* boy ( x _ 7 ) ; * potato ( x _ 9 ) ; think . agent ( x _ 1 , Olivia ) AND think . ccomp ( x _ 1 , x _ 5 ) AND girl ( x _ 4 ) AND mail . agent ( x _ 5 , x _ 4 ) AND mail . recipient ( x _ 5 , x _ 7 ) AND mail . theme ( x _ 5 , x _ 9 ) AND potato . nmod . in ( x _ 9 , x _ 12 ) AND room ( x _ 12 )