关于冠词的问题

问题描述:

关于冠词的问题
"Football is ___sport I love,___sport that has given me so much,"
A a;the B a;a C /;a D the;the
前一个可以理解,后一个,为什么用a呢?

a表示泛指,并没有特指或是强调.本句中为介绍一种运动,类似的还有
At last,he became the manager,a position he had always dreamt of.
a position用来解释manager.