The number of medical schools reached 18 in the early 1990s and ______ around that level ever since.( )
are remaining
have remained
is remaining
has remained
________ 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.
The most popular food ______ on menus in western countries is hamburger.