—I met your uncle on my way to school this morning.—Ah? You _____ be joking. He flew to Germany yesterday evening!
He _____ himself in Shanghai.
I was about to leave _____ the telephone rang.
Children under 10 are not permitted _____ the film.
All he was thinking about was ____ he would do with the big sum of money his father gave him.
23. The harder we work at our lessons, _____.