The student completed this experiment to make come true ______ Professor Joseph had said.( )
that
what
when
where
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.
There is no greater pleasure than running on the playground, ____ after a ball.