kids are walking across a field in red clothes.
The kids were walking across the field.
The first sentence states that the kids are walking across a field and the second sentence states the same thing, that the kids were walking across the field.
exists e1 s1 x1 x2 x3.(in(e1,x3) & n_clothes(x3) & a_red(s1) & Theme(s1,x3) & across(e1,x2) & n_field(x2) & Actor(e1,x1) & v_walk(e1) & n_kid(x1))
exists e1 x1 x2.(n_field(x2) & n_kid(x1) & across(e1,x2) & Actor(e1,x1) & v_walk(e1))