While the dog, you should take care not to Otherwise, it may be dangerous to strangers.
| A．walking; get it loose |
| B．walk; be loose |
| C．walking for; get it loose |
| D．train; get it run |
________ you may have，you should gather your courage to face the challenge.
| A．However a serious problem |
| B．What a serious problem |
| C．However serious a problem |
| D．What serious a problem |
—Haven’t seen Lucy recently，what’s happened?
—Oh，it’s more than two months ________ she worked here.
| A．which | B．that |
| C．before | D．since |
________you’ve experienced it，you can’t understand how I felt.
| A．Once | B．Because |
| C．Unless | D．While |
I had no idea of the exact address of Xinhua High School ________I was outside its front gate.
| A．when | B．after |
| C．until | D．because |
John plays basketball well，________ his favorite sport is badminton.
| A．so | B．or | C．yet | D．for |