It suddenly ______ to me that we could use a computer to do the job.
| A．took place | B．occurred | C．came about | D．happened |
______ environmental damage is done，it takes many years for the ecosystem to recover．
| A．Even if | B．If only |
| C．As if | D．Once |
----- I'm going to San Francisco for a couple of days.
------ ________. I wish I could get away for a while.
| A．It doesn't matter | B．Forget it |
| C．I really envy you | D．I can't agree more |
It’s surprising that your brother _____ Russian so quickly—he hasn’t lived there very long.
| A．picked up | B．looked up |
| C．put up | D．made up |
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 such a nice place," Mother said as she sat at the table______ for customers.
| A．to be reserved | B．having reserved |
| C．reserving | D．reserved |