By the time he arrives in Beijing, we _________ here for two days.

A. will be arriving           B.have been staying      

C. have stayed              D. will have stayed

By the time he arrives in Beijing, we ______ here for two days.

By the time he arrives in Beijing, we ______ here for two days.

A．will have stayed                        B．will be staying

C．have been staying                       D．have stayed

By the time he arrives in Beijing, we ______ here for two days.

　 　 A. will have stayed　　 B. shall stay　　

C. have been staying　 D. have stayed