A defender attempts a tackle in rugby.
The defender is at practice.
WE DON'T KNOW HE IS AT PRACTICE.
all x1.(n_tackle(x1) -> exists x2 x3 x4.(a_topic(x2) & in(x2,x4) & n_rugby(x4) & for(x2,x1) & n_attempt(x2) & of(x2,x3) & n_defender(x3)))
exists p1 x1.(n_defender(x1) & exists x2.(at(x1,x2) & n_practice(x2)))