It is not a problem ______ we can win the battle;it's just a matter of time.( )
whether
why
when
where
Xiamen—Shenzhen High Speed Railway opened to traffic on Dec.28 last year, _______ the two of China’s economic zones.
________ with the courage and determination of the young cancer patient, many people left messages in his microblog, encouraging him to fight with the disease.
Having taken our seats, _______.
The students listened carefully to the teacher with their eyes _____ on the blackboard.
With our knowledge practice , we can make contribution to our society.