______life began on the earth is one of the biggest puzzles to scientists.
| A．How | B．What | C．Where | D．That |
The computer was used in teaching. As a result, not only _____, but students became more interested in the lessons.
| A．saved was teachers’ energy | B．was teachers’ energy saved |
| C．teachers’ energy was saved | D．was saved teachers’ energy |
Have you got any particular plans for the coming holiday?
Yes. _____, I’m going to visit some homes for the old in the city.
| A．If ever | B．If busy | C．if anything | D．if possible |
Would you mind not picking the flowers in the garden? They are ______ everyone’s enjoyment.
| A．in | B．at | C．for | D．to |
Up to now, the program ______ thousands of children who would otherwise have died.
| A．would save | B．saves | C．had saved | D．has saved |
First impressions are the most lasting. After all, you never get ______ second chance to make ______ first impression.
| A．a; the | B．the; the | C．a; a | D．the; a |