— the team finished most of their research work?
—Yes, but the rest rather difficult.
| A．Has, are | B．Has, is | C．Have, are | D．Have, is |
According to scientists, our mental abilities begin to______from the age of 27 after reaching the highest level at 22.
| A．differ | B．shrink | C．fail | D．decline |
"It's a such nice place," Mother said as she sat at the table________ for customs.
| A．to be reserved | B．Living reserved | C．reserving | D．reserved |
The research lacks evidence, and therefore, its conclusions are doubtful.
| A．solid | B．fierce | C．severe | D．potential |
We live in an age more information is available with greater ease than ever before.
| A．why | B．when | C．to whom | D．on which |
I think Tom, as the head of a big department, should either study regularly or______ his job.
| A．quits | B．to quit | C．quitting | D．quit |