They were surprised that a child worked out the problem _____ they themselves couldn’t.
| A．once | B．then | C．if | D．while |
The heavy rain made his business _______ a great loss.
| A．suffer | B．suffer from | C．suffering | D．suffering from |
To the parents’ worry, some middle school students are ______ computer games and completely forget their studies.
| A．crazy about | B．very fond of | C．concerned for | D．serious about |
It was in 1969 ______ two Americans went to the moon by spaceship.
| A．when | B．that | C．at that time | D．just then |
My mother insisted that I _____to school on foot.
| A．went | B．goes | C．go | D．going |
Since Margot found it difficult to settle in a new place, she felt ______ that the family had to move.
| A．upset | B．crazy | C．happy | D．easy |