she has made up her mind to go into business when she leaves her college

问题描述:

she has made up her mind to go into business when she leaves her college
为什么主句用完成时态?

强调影响,说明她现在仍然有这种想法
而过去式也是可以的,不过只是说明了一个动作而已,现在还有没有这个想法我们不知道