Li-ping is said      in Beijing, but we don’t know what school she worked in．

1. A.
   to have worked
2. B.
   to work
3. C.
   to be working
4. D.
   to have been working

Li-ping is said      in Beijing, but we don’t know what school she worked in．

       A．to have worked           B．to work

     C．to be working       D．to have been working