单项选择题
A．to study industrial management B．to buy and read more mystery books C．to do market research on book business D．to work harder to save money for the bookstore
A．day and night, right through the week B．two or three times a week C．at any time of the day, but not at night D．right through the day, two or three times a week
A．Five years. B．Almost four years. C．Almost six years. D．Ten years.