A man sits in a boat on a lake.
a man is indoors
A boat on a lake is outdoors and not indoors so a man cannot sit in a boat on a lake and still be indoors.
exists e1 x1 x2 x3.(on(e1,x3) & n_lake(x3) & in(e1,x2) & n_boat(x2) & Actor(e1,x1) & v_sit(e1) & n_man(x1))
exists p1 x1.(exists x2.((x1 = x2) & n_indoor(x2)) & n_man(x1))