_______in the city for thirty years, the old man moved back to the countryside.
| A．Having worked | B．Working | C．To have worked | D．To work |
Electricity is not easy _________ when an earthquake happens.
| A．to get | B．to be got | C．getting | D．get |
Mary wanted to ______ her experiment, but her parents encouraged her to continue.
| A．give up | B．give in | C．give out | D．give away |
He is _________ and I believe he can keep the secret for you.
| A．determined | B．stubborn | C．reliable | D．frightened |
I hear that you will go to Beijing this afternoon. Who ______ you off at the airport?
| A．sees | B．saw | C．is seeing | D．has seen |
—How long have you been working as an assistant here?
—__________I finished middle school.
| A．Ever since | B．Before | C．After | D．When |