Many people wearing blue jackets are marching down a street.
Many people are playing trumpets while marching down a street
People marching down a street would not necessarily be playing trumpets.
exists e1 e2 s1 x1 x2 x3 x4.(down(e2,x4) & n_street(x4) & Actor(e2,x1) & v_march(e2) & Theme(e1,x3) & Actor(e1,x2) & v_wear(e1) & n_jacket(x3) & a_blue(s1) & Theme(s1,x3) & (x1 = x2) & n_people(x1) & n_quantity(x1))
exists e1 e2 s1 x1 x2 x3.(while(e1,e2) & a_down(s1) & Manner(e2,s1) & Theme(e2,x3) & Actor(e2,x1) & v_march(e2) & n_street(x3) & Theme(e1,x2) & Actor(e1,x1) & v_play(e1) & n_trumpet(x2) & n_people(x1) & n_quantity(x1))