A dog walking on a beach
The pet is sniffing the sea air.
Sentence 1 is missing sniffing the sea air
exists x1 x2 x3.(a_topic(x1) & on(x1,x3) & n_beach(x3) & n_walking(x1) & of(x1,x2) & n_dog(x2))
exists e1 x1 x2 x3.(n_air(x2) & of(x2,x3) & n_sea(x3) & n_pet(x1) & Theme(e1,x2) & Actor(e1,x1) & v_sniff(e1))