31. I still remember ______ to the hospital, supported by my class teacher when I was ill at school.
He took off his coat, _____ all his pockets, but couldn’t find his key.
He will spend six hours at his desk _______ he finishes his composition.
--- What is the matter with the pen? --- The ink _______come out.
Wang Ping can’t be in the bedroom, ?
What a pretty girl, ?