There is ________dark stain(污渍) on my coat. Who left it—- It’s me, Dad. I did it just for ______ fun.

With the development of science and technology, the prices of TV sets have ________.

What an _____ question it sounds! Even my daughter can answer it ________.

1–Doyou know____ he will stay in America –Ten weeks.

Jane is in a hurry because the train to the airport leaves _______ half an hour.