.
If this computer does not give complete satisfaction, please return it to the maker stating when and where it was ________.
| A．designed | B．operated | C．purchased | D．made |
We entered the café and sat down by the window, waiting ________.
| A．to serve | B．to be served |
| C．serving | D．served |
With so many exercises ________， the students are having a hard time.
| A．finished | B．finishing |
| C．to finish | D．being finishing |
Whom do you expect to have ________ the baggage to the airport?
| A．deliver | B．to deliver |
| C．delivered | D．delivering |
The airport is far from here, and ________ there on time, you'd better take a taxi.
| A．get | B．to get |
| C．getting | D．got |
The old couple walked rather slowly, and could be seen, from time to time, to stop and rest, ________ out to sea.
| A．to be staring | B．stared |
| C．having stared | D．staring |