单项选择题
A. Every 5 minutes. B. Every 10 minutes. C. Every 15 minutes.
A."O" levels and "A" levels. B."O" levels and "H" levels. C."A" levels.
A. Because they could move into new flats with more rooms than their old ones. B. Because they liked to move into new flats. C. Because they could move into new flats not far from their old homes.