A large crowd of people walk, casually, across an elevated road or bridge.
The people are swimming across the lake.
People can't walk and swim at the same time.
exists e1 s1 s2 s3 x1 x2 x3.(across(e1,x3) & (n_road(x3) | n_bridge(x3)) & a_elevated(s3) & Theme(s3,x3) & a_casually(s2) & Manner(e1,s2) & Actor(e1,x1) & v_walk(e1) & of(x1,x2) & n_people(x2) & n_crowd(x1) & a_large(s1) & Theme(s1,x1))
exists e1 x1 x2.(n_lake(x2) & n_people(x1) & across(e1,x2) & Actor(e1,x1) & v_swim(e1))