A man in a red helmet holds a bullhorn.
A man who was wearing a red helmet was also holding a bullhorn.
'' A man who was wearing a red helmet '' is  a rephrasing of ''  A man in a red helmet''.
exists e1 s1 x1 x2 x3.(Theme(e1,x3) & Actor(e1,x1) & v_hold(e1) & n_bullhorn(x3) & in(x1,x2) & n_helmet(x2) & a_red(s1) & Theme(s1,x2) & n_man(x1))
exists e2 e1 s1 s2 x1 x2 x3 x4.(a_also(s2) & Manner(e2,s2) & Theme(e2,x4) & Actor(e2,x1) & v_hold(e2) & n_bullhorn(x4) & Theme(e1,x3) & Actor(e1,x2) & v_wear(e1) & n_helmet(x3) & a_red(s1) & Theme(s1,x3) & (x1 = x2) & n_man(x1))