The glass doors have taken the place of the wooden ones at the entrance,_____ in the natural light during the day.
| A．to let | B．letting | C．let | D．having let |
He felt _________ when he found a stranger _________ about at the gate of the police station.
| A．puzzling; hung | B．puzzled; hung |
| C．puzzling; hanging | D．puzzled; hanging |
____ since the night before, I felt very hungry.
| A．Having eaten anything | B．Not having eaten anything |
| C．I hadn’t eaten anything | D．Not eating anything |
_____ with the accident, he was forced to resign.
| A．Concerned | B．Concerning |
| C．Having concerned | D．Be concerned |
They use computers to keep the traffic smoothly．
| A．being run | B．run | C．to run | D．Running |
All flights ________called off because of the terrible weather, they had to go there by train.
| A．were | B．having been | C．being | D．had been |