Whenever I see Sally, I always ______her mother.
| A．think about | B．think for | C．think out | D．think of |
People try to avoid public transportation delays by using their own cars, and this _____ further problems.
| A．in short | B．in case | C．in doubt | D．in turn |
Although ____ my opinion, the old professor didn’t come up with his own.
| A．against | B．on | C．for | D．in |
The field research will take Joan and Paul about five months;it will be a long time_____we meet them again.
| A．after | B．before | C．since | D．when |
My parents live in a small village. They always keep candles in the house ___ there is a power cut.
| A．if | B．unless | C．in case | D．so that |
It is difficult for us to learn a lesson in life _____we’ve actually had that lesson.
| A．until | B．after | C．since | D．when |