Last year the number of students who graduated with a driving licence reached 200 000

问题补充：

单项选择题:

Last year the number of students who graduated with a driving licence reached 200,000, a(n) () of 40,000 per year.

A. average B. number C. amount D. quantity

答案：

答案：A

解析： 句意：去年毕业时就有驾照的学生数量已达到20万，平均每年4万。average平均，平均数；a number of许多，大量，修饰可数名词；an amount of许多，大量，与不可数名 词连用；a quantily of许多，大量的，修饰可数和不可数名词。根据句意，选A。