I ___________ to phone her all day, but whenver I phone her, the line is engaged.
| A．tried | B．had been trying | C．have tried | D．have been trying |
31. I still remember ______ to the hospital, supported by my class teacher when I was ill at school.
| A．to be taken | B．being taken | C．to take | D．taking |
He hurried to the airport with his friends only ______ that all the film stars they liked best had been picked up by their company.
| A． to tell | B．to be told | C． telling | D．told |
23. Mr. Smiths was busy writing a story, only ______ once in a while to smoke a cigarette.
| A．to stop | B．to have stopped | C．being stopped | D．stopping |
It’s reported that energy drinks are not allowed ___ in Australia.
| A．to be making | B．to be made | C．to make | D．to have been made |
The experiment shows that proper amounts of exercise, if regularly, can improve our health.
| A．being carried out | B．carrying out | C．carried out | D．to carry out |