20.There used__________a post office at the corner of the street.
| A．to be | B．to being | C．to have | D．to having |
Seeing the owner of the house coming, away __________.
| A．the naughty boys run |
| B．did the naughty boys run |
| C．the naughty boys ran |
| D．ran the naughty boys |
Look! __________.
| A．Here he comes | B．Here comes he |
| C．He came here | D．Here does he come |
Don’t get off the bus until it __________.
| A．has stopped | B．stopped |
| C．will stop | D．shall stop |
That suit __________ over 60 dollars.
| A．has costed | B．costed |
| C．is costed | D．cost |
Tom __________ into the house when no one __________.
| A．slipped; was looking | B．slipped; had looked |
| C．had slipped; looked | D．was slipping; looked |