In the United States, there is always flow of people to areas of country where more jobs can be found.
A. a; the
B. the; a
C. the; the
D. a; a
网友回答
(答案→)A. a; the
B. the; a
C. the; the
D. a; a
解析： a flow of people 指“流动的一群人”，the country 特指前面的the United States.