I don’t know who invented _____digital camera, and it’s really _____ most useful invention.
| A．the; a | B．the; the | C．a; a | D．不填；不填 |
The young writer_____his success to his teacher’s encouragement.
| A．paid | B．cost | C．gave | D．owed |
When you phoned me,I was having a meeting,otherwise I_______your call.
| A．answered | B．would answer | C．had answered | D．would have answered |
_________I went to the US,I visited many cities.
| A．First time | B．For the first time | C．The first time | D．By the first time |
He_______gardening after his retirement.
| A．ended up | B．turned up | C．put up | D．took up |
Traffic on the bridge was_______for an hour because of the accident.
| A．held up | B．held on | C．held back | D．kept on |