Four boys pose for the camera.
Four boys are shooting guns at each other.
If you are shooting, you are not posing because you are moving. Shooting a camera and shooting a gun are two different actions.
exists e1 x1 x2.(n_camera(x2) & for(e1,x2) & Actor(e1,x1) & v_pose(e1) & n_boy(x1) & card_eq_4(x1))
exists e1 x1 x2.(all x3.(n_other(x3) -> at(e1,x3)) & Theme(e1,x2) & Actor(e1,x1) & v_shoot(e1) & n_gun(x2) & n_boy(x1) & card_eq_4(x1))