Two students at work in a science class.
They are inside
Two or more students amounts to "they" and a classroom is  usually on the inside of a building.
exists x1 x2 x3 x4.(a_topic(x1) & at(x1,x2) & in(x2,x3) & n_class(x3) & of(x3,x4) & n_science(x4) & n_work(x2) & n_student(x1) & card_eq_2(x1))
exists s1 s2 x1.(n_thing(x1) & a_inside(s2) & Manner(s1,s2) & Theme(s1,x1) & a_event(s1))