——Do you know what your problem is?
—Yes. I always overwork to ________ for lost time.
| A．sit up | B．keep up |
| C．make up | D．hold up |
With two children ______ middle school in the nearby town now, the parents are working hard.
| A．to attend | B．attending | C．attended | D．having attended |
Having answered the phone, I couldn’t but ______ what would happen next.
| A．wondering | B．wondered | C．wonder | D．to wonder |
All of us remember the earthquake that ______ Wenchuan in 2008.
| A．attacked | B．struck | C．knocked | D．exploded |
Paul had to write a history paper, _____ he couldn’t find time to do it.
| A．but | B．so | C．because | D．if |
They want to know ______do to help us.
| A．what can they | B．what they can | C．how they can | D．how can they |