How can you expect him to make any improvement ________ you never give him an opportunity to have a try?
. We should consider what use can _______ such a book.
Once he ______ his mind, nothing can be done to ________ his mind.
Many questions _____ at the meeting, but he answered none.
. The old man, who _______ the World War II, is Peter’s grandfather.
. Students should _____ everything important their teachers give in class.