The security guard is smiling.
The security guard is over the age of 18.
The security guard that is smiling is over the age of 18.
exists e1 x1 x2.(n_guard(x1) & of(x1,x2) & n_security(x2) & Actor(e1,x1) & v_smile(e1))
exists p1 x1 x2 x3.(n_age(x3) & n_guard(x1) & of(x1,x2) & n_security(x2) & exists x4.(over(x1,x3) & of(x3,x4) & n_date(x4) & a_date_day_18(x4) & a_date_day_18(x4)))