问题补充:
Last year the number of students who graduated with a driving license reached 200,000, a(n) of 40,000 per year.
A. average
B. number
C. amount
D. quantity
答案:
(答案→)A. average
B. number
C. amount
D. quantity
解析:短语辨析。An average of 平均;句意:去年取得驾照的毕业生的数量达到了20万,平均每年4万。