__________ parents say and do has a life-long effect on their children.
| A．That | B．Which |
| C．What | D．As |
According to a new study by a French university, learning ______ second language can lead to ______ increase in your brain power.
| A．a; the | B．a; an | C．the; the | D．the; an |
Their classroom is _____ than ours, that is to say, their classroom is as small as ours.
| A．much bigger | B．much smaller | C．no bigger | D．less small |
It was _____ it raised so many difficult questions _____ the book took a long time to come out.
| A．that; that | B．since; which | C．because; that | D．because; which |
It is sometimes of great _____ to explain to the patient what is happening.
| A．technique | B．signal | C．importance | D．freedom |
The failure of his plan made him _____ that he had made a great mistake in working out the plan.
| A．be aware | B．aware of | C．aware | D．be aware of |