--when did you start to collect stamps?--l got my ---stamp when l was --- years old

题目

--when did you start to collect stamps?--l got my ---stamp when l was --- years old
a one ;seven
b one; seventh
c first;seventh
d first; seven
说理由!

答案

选D.
首先,说年龄时用基数词,不用序数词,排除b、c.
其次,问的是何时开始,用first含有“第一”的意思,与问句相符；而one则可表示任何一个,与问句的“开始”不符.