A man on a steep incline wearing a white shirt is working on a roof, with lots of debris all around.
a man on an incline works
A man working on a roof can be more generally referred to as just working. The details of his clothing can be left out without altering the point of the sentence.
exists e1 e2 s1 s2 x1 x2 x3 x4 x5 x6 x7.(with(e2,x6) & of(x6,x7) & n_all(x7) & r_around(x7) & n_debris(x7) & n_lot(x6) & on(e2,x5) & n_roof(x5) & Actor(e2,x1) & v_work(e2) & on(x1,x2) & Theme(e1,x4) & Actor(e1,x3) & v_wear(e1) & n_shirt(x4) & a_white(s2) & Theme(s2,x4) & (x2 = x3) & n_incline(x2) & a_steep(s1) & Theme(s1,x2) & n_man(x1))
exists e1 x1 x2.(Actor(e1,x1) & v_work(e1) & on(x1,x2) & n_incline(x2) & n_man(x1))