As we came to the work site, the workers were seen _______the new house.
| A．building | B．build | C．built | D．to build |
With a lot of difficult problems ________, the newly-elected president is having a hard time.
| A．settled | B．setting | C．to settle | D．being settled |
Tony was very unhappy for _______ to the party.
| A．having not been invited | B．not having invited |
| C．having not invited | D．not having been invited |
Though ________ money, his parents managed to send him to university.
| A．lacked | B．lacking of | C．lacking | D．lacked in |
The research is so designed that once _______ nothing can be done to change it.
| A．begins | B．having begun | C．beginning | D．begun |
“What do you think made Mary so upset?” “_______ her new bike.”
| A．As she lost | B．Lost | C．Losing | D．Because of losing |