---We’ve seen many more days of blue skies recently. ---True. But back in 1998, ________ Beijing started its “Defending the Blue Sky” program, the city only ________ about 100 days a year.
. In order to learn the of the family business, Bill took a job as messenger boy in one of the offices.
A. ins and outs B. dos and don’ts C. heads and tails D t’s and i’s