A man who was stuck in the tree.
A man was in that tree.
We do not know which tree, " that " infers we do.
exists e1 x1 x2 x3.(n_tree(x3) & a_topic(x1) & in(e1,x3) & Theme(e1,x2) & v_stick(e1) & (x1 = x2) & n_man(x1))
exists p1 x1 x2.(n_tree(x2) & in(x1,x2) & n_man(x1))