Though scientists get closer to understanding why we age， the reason for different aging rates among individuals remains only __________ understood．
A.concretely B.thoroughly
C.vaguely D.flexible
—Didn’t you have a good time at the party?
—Of course I did.As a matter of fact,I had such fun that time seemed to_____so quickly.
A.go by B.go away
C.go out D.go over
What shall we use for power when all the oil in the world has been _____？
A.given out B.put out C.held up D.used up
His idea of having weekly family meals together，which seemed difficult at first，has ______ many good changes in their lives.
A.got through B.resulted from C.turned into D.brought about
She ________ Japanese when she was in Japan. Now she can speak it freely.
A.picked out. B.made out C.made up D.picked up
The computer system____ suddenly while he was searching for information on the Internet.
A.broke out B.broke in
C.broke up D.broke down
