--How often do you eat out?
--___, but usually once a week.
| A．I have no idea | B．It depends |
| C．As usual | D．Generally speaking |
.It _____we had stayed together for a couple of weeks ____I found we had a lot in common.
| A．was until; when | B．was until; that |
| C．wasn’t until; when | D．wasn’t until; that |
.In my opinion, life in the twenty-first century is much easier than _______.
| A．that used to be | B．it is used to | C．it was used to | D．it used to be |
.He said he _________ experiments those days.
| A．was doing | B．had been doing | C．has been doing | D．is doing |
There was a heavy curtain ________ the light.
| A．blocking out | B．preventing from | C．blocking in | D．taking off |
. These old buildings possibly __________ the Ming Dynasty.
| A．dated back to | B．date back to | C．date back | D．are dated back to |