In the experiment we kept a watchful eye ________ the developments and recorded every detail.
| A．in | B．at |
| C．for | D．on |
______ apple fell from the tree and hit him on ______ head.（）
| A． | An; the | B． | The; the | C． | An; 不填 | D． | The; 不填 |
Are you all right?
| A． | That's OK | B． | I think so | C． | Take it easy | D． | It's very kind of you |
The terrible accident almost_____ the driver his life.
| A．valued | B．counted | C．took | D．cost |
Once out of the earth’s gravity, the astronaut is____by the problem of weightlessness.
| A．affected | B．effected | C．related | D．offered |
The beauty of the place ______ them to pause in their hike and rest a while.
| A．allowed | B．switched | C．invited | D．addicted |