According to recent U. S. Statistics Yearbook, Americans spend $16 billion a year on credit cards and there are already 590 million in ().

单项选择题Other guests at yesterday's opening ceremony, which was broadcast () by the radio station, included the Governor and the Mayor.

A. alive
B. live
C. lively
D. living

单项选择题Consumption of domestic fuel oil () from 150 gallons a month at the height of winter to practically nothing in July and August.

A. differs
B. shifts
C. varies
D. switches