The time he has devoted in the past ten years ________the disabled is now considered _______of great value.
| A．to help; being | B．help; to be | C．to helping; to be | D．helping; being |
Many studentspreparing for the midterm examination.
| A．are engaging in | B．are engaging themselves |
| C．are engaging themselves | D．are engaged in |
________ from space, the earth , with water_______ seventy percent of the surface , looks like a blue ball.
| A．Seen ; covered | B．Seen ; covering |
| C．seeing ; covering | D．Seeing ; covering |
The news has spread all over the country _____ the spaceship succeeded in returning to the earth.
| A．that | B．which | C．whether | D．what |
— What made her so sad？
— _____ she failed in the examination.
| A．That | B．Because | C．As | D．Since |
Honestly speaking, it is my teacher’s _____ that made me finally take up my present career
as 
a biology researcher.
| A．advantage | B．influence | C．taste | D．guard |