They have already been to the place ____ their ancestors lived .
A. which B. where C. when
—Where is Jack?
—I noticed that he ________the teacher’s office just now.
| A．went into | B．goes into | C．was going into | D．is going to |
—Don’t worry. Your uncle is coming to help you.
—________he doesn’t come?
| A．What if | B．Why not | C．What about | D．What for |
My friend’s flight had taken off _________ I got to the airport to see him off.
| A．while | B．after | C．before | D．until |
The monkey was seen _________off the tall tree.
| A．jump | B．jumps | C．jumped | D．to jump |
—What do you think about the idea?
—I am really against _________ a running race in the street.
| A．to have | B．having | C．to having | D．have |