A table full of high school aged kids are performing science experiments in three groups of four.
The high school kids wear aprons over their uniforms as they perform experiments at the table.
Not all science experiments involve the use of aprons.  Not all High Schoolers wear uniforms.  Not all experiments must be performed at a table.
exists e2 e1 s1 s2 x1 x2 x3 x4 x5 x6 x7 x8.(Theme(e2,x5) & Actor(e2,x1) & v_perform(e2) & in(x5,x7) & of(x7,x8) & n_thing(x8) & card_eq_4(x8) & n_group(x7) & card_eq_3(x7) & n_experiment(x5) & of(x5,x6) & n_science(x6) & of(s1,x3) & n_kid(x3) & Theme(e1,x3) & v_age(e1) & of(x3,x4) & n_school(x4) & a_high(s2) & Theme(s2,x3) & Theme(s1,x2) & a_full(s1) & (x1 = x2) & n_table(x1))
exists e1 p1 s1 x1 x2 x3 x4 x6.(n_table(x6) & n_thing(x1) & n_thing(x1) & n_uniform(x4) & of(x4,x1) & n_kid(x1) & of(x1,x2) & n_school(x2) & a_high(s1) & Theme(s1,x1) & exists e2 x5.(Theme(e2,x5) & Actor(e2,x1) & v_perform(e2) & at(x5,x6) & n_experiment(x5)) & as(e1,p1) & over(e1,x4) & Theme(e1,x3) & Actor(e1,x1) & v_wear(e1) & n_apron(x3))