The money he has contributed in the past years to ______ the disabled is now considered to be of great value.
| A．help | B．helping, | C．having helped | D．being helped |
Encourage your children to try new things, but try not to ___ them too hard.
| A．draw | B．strike | C．rush | D．push |
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 |
The children all turned ____ the famous actress as she entered the classroom. 
| A．looked at | B．to look at |
C．to looking at | D．look at |
Edward, you play so well. But I ______ you played the piano. 
| A．didn’t know | B．hadn’t known |
C．don’t know | D．haven’t known |
She brought with her three friends, none of ______ I had ever met before. 
| A．them | B．who | C．whom | D．these |