When Mary arrived she found all her children ______ for nearly two hours.
| A．have gone to sleep | B．fell asleep |
| C．was falling asleep | D．had been asleep |
Only when you leave your parents for college education _______ how much you love them.
| A．do you realize | B．you realize | C．you will realize | D．will you realize |
The cause he had devoted himself to _______ a perfect success.
| A．proving | B．proved | C．was proved | D．has been proved |
Many experts believe that teachers’ development is _____ the key to better education lies.
| A．that | B．what | C．where | D．which |
Evidence has been piled up_____drinking water after getting up in the morning contributes to one’s health.
| A．what | B．which | C．if | D．that |
There is a great deal of research ___that music activities engage different parts of the brain.
| A．indicate | B．indicating | C．to indicate | D．to be indicating |