A line of men in yellow uniforms help carry a pipe, while the man carrying the nozzle sprays liquid from the pipe.
Firefighters at work
While descriptive of Firefighters, there may be another reason for the men with the pipe.  If they are firefighters, they may be practicing for a competition and not at work.
exists e1 p1 p2 s1 x1 x2 x3 x6 x8.(n_pipe(x8) & n_nozzle(x6) & exists e3 e4 x5 x7.(from(e4,x8) & Theme(e4,x7) & Actor(e4,x2) & v_spray(e4) & n_liquid(x7) & Theme(e3,x6) & Actor(e3,x5) & v_carry(e3) & (x2 = x5)) & n_man(x2) & n_man(x2) & while(e1,p2) & exists e2 x4.(Theme(e2,x4) & Actor(e2,x1) & v_carry(e2) & n_pipe(x4)) & Topic(e1,p1) & Actor(e1,x1) & v_help(e1) & of(x1,x2) & in(x2,x3) & n_uniform(x3) & a_yellow(s1) & Theme(s1,x3) & n_line(x1))
exists x1 x2.(a_topic(x1) & at(x1,x2) & n_work(x2) & n_firefighter(x1))