People try to avoid public transportation delays by using their own cars, and this __________ creates further problems.
| A．in short | B．in case |
| C．in doubt | D．in turn |
Those _____ cannot answer all three riddles will be condemned to death.
| A．that | B．who |
| C．which | D．what |
Some people get in touch with each other by mobile phones__________ others keep contact with each other by e-mail.
| A．when | B．before | C．while | D．since |
It’s much easier to make friends ____ you have similar interests.
| A．unless | B．when |
| C．even though | D．so that |
I graduated from college twenty years ago and I ____________ as an English teacher in this middle school ever since.
| A．worked | B．have been working |
| C．had worked | D．was working |
The girl has a great interest in sport and ____ badminton classes twice a week over the last three years.
| A．took | B．is taking |
| C．takes | D．has been taking |