The security guard is smiling.
The security guard is yelling.
The security guard is either  smiling or yelling.
exists e1 x1 x2.(n_guard(x1) & of(x1,x2) & n_security(x2) & Actor(e1,x1) & v_smile(e1))
exists e1 x1 x2.(n_guard(x1) & of(x1,x2) & n_security(x2) & Actor(e1,x1) & v_yell(e1))