The computer system _____ suddenly while he was searching for information on the Internet.
| A．broke down | B．broke out | C．broke up | D．broke in |
Our country ______ great changes in the last 30 years and it is no longer it used to be.
| A．went through; what | B．went through; that |
| C．has experienced; that | D．has experienced; what |
Every student as well as teachers who ______ to visit the museum ______ asked to be at the school gate on time.
| A．is; is | B．are; are | C．is; are | D．are; is |
______ about the missing boy’s safety, the police stepped up their search.
| A．Concerning | B．Concerned | C．Being concerned | D．Concern |
I don’t feel well; I think I’m ______ with the flu.
| A．going on | B．getting in touch | C．putting off | D．coming down |
We would have called a taxi yesterday if Haroldus a ride home.
| A． | didn't offer | B． | wouldn't offer |
| C． | hasn't offered | D． | hadn't offered |