it'll have to pay systematic attention to graduating minorities,not just enrolling them.语法?

问题描述:

it'll have to pay systematic attention to graduating minorities,not just enrolling them.语法?
请问为什么not just enrolling them.enroll要用动名词形式呢? 不能用not just enroll them

graduating minorities 和 enrolling them 是平行的..It'll have to pay systematic attention to graduating minorities,not just enrolling them.=it'll have to pay systematic attention to graduating minoriti...