--Has the train arrived yet?---No, it ought to ___ twenty minutes ago.
| A．arrive | B．have arrived | C．be arriving | D．be arrive |
China has promised to revise its existing regulations and __________ new policies according to WTO requirements.
| A．forming | B．to form |
| C．to be forming | D．have formed |
__________ the employees’ working efficiency, the supervisor will allow them to have a coffee break.
| A．Improving | B．To improve |
| C．Having improved | D．Improved |
There are hundreds of visitors __________ in front of the Art Gallery to have a look at Van Gogh’s paintings.
| A．waited | B．to wait |
| C．waiting | D．wait |
The parents suggested __________ in the hotel room but their kids were anxious to camp out during the trip.
| A．sleep | B．to sleep |
| C．sleeping | D．having slept |
Mary, __________ here — everybody else, stay where you are.
| A．come | B．comes |
| C．to come | D．coming |