Class sign ups in full swing.
People are signing up for english classes.
You can't assume people are signing up for english when it could be math. Also, all classes are implied through that first sentence.
exists s1 x1 x2 x3 x4.(a_topic(x1) & in(x1,x4) & n_swing(x4) & a_full(s1) & Theme(s1,x4) & Time(x1,x3) & n_up(x3) & n_sign(x1) & of(x1,x2) & n_class(x2))
exists e1 s1 s2 x1 x2.(for(e1,x2) & n_class(x2) & a_english(s2) & Theme(s2,x2) & a_up(s1) & Manner(e1,s1) & Actor(e1,x1) & v_sign(e1) & n_people(x1))