There are several research centers in China ________ a certain disease called Bird Flu is
being studied.
| A．which | B．where | C．when | D．what |
_______ any need for us to discuss the problem again since it has already been removed？
| A．Has it | B．Has there | C．Is it | D．Is there |
After several years, he changed a lot and looked different from _______he used to be.
| A．whom | B．what | C．which | D．that |
The teacher asked more ______to prevent the students’ eyes from being injured.
| A．to do | B．done | C．to be done | D．being done |
It was decided to _______ the search when there was no hope of finding the missing child alive.
| A．call off | B．let off | C．put off | D．round off |
The story is very interesting, and it is _______.
| A．well worth reading | B．well worthy of reading |
| C．very worthy reading | D．worth to read |