A guy surfing in the ocean.
A man is swimming in the lake.
An ocean and a lake are two different places
exists x1 x2 x3.(n_ocean(x3) & a_topic(x1) & in(x1,x3) & Time(x1,x2) & n_surfing(x2) & n_guy(x1))
exists e1 x1 x2.(n_lake(x2) & in(e1,x2) & Actor(e1,x1) & v_swim(e1) & n_man(x1))