The field is fenced in.
There is a fence around the perimeter of the field.
Fence around the perimeter is a rephrasing of fenced it.
exists e1 s1 x1.(n_field(x1) & a_in(s1) & Manner(e1,s1) & Theme(e1,x1) & v_fence(e1))
exists p1 x1 x3 x4.(n_field(x4) & n_perimeter(x3) & exists x2.((x1 = x2) & around(x2,x3) & of(x3,x4) & n_fence(x2)))