Not all of us know the difference ________ wheat, oats and barley.
—I'm not finished with my dinner yet.—But our friends ________ for us.(2010·北京)
It's really time I went home but I'm enjoying myself, so I ________ here a bit longer.
The sky is clouding over;we can see there ________ a rainstorm.
Close the door of fear behind you,and you ________ the door of faith open before you.(2012·湖南)
—Ann is in hospital.—Oh,really?I ________ know.I ________ go and visit her.