A terrible earthquake happened in that district at the end of 2004, ____ many countries in the world paid close attention to this.
| A．where | B．when | C．which | D．what |
________you’ve experienced it，you can’t understand how I felt.
| A．Once |
| B．Because |
| C．Unless |
| D．While |
________ 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 |
Paul was not allowed to work he was fully recovered from the flu.
| A．even if |
| B．whether |
| C．because |
| D．until |
She cared more about her students than her own health. That’s why two years passed _____ she was treated for breast cancer.
| A．since |
| B．before |
| C．after |
| D．until |
It was 1995 __________ we began to develop the new computer system.
| A．when |
| B．which |
| C．since |
| D．that |