澳大利亚的绿卡必须要读两年研究生以上才能申请？

不能，2年政策要求如下，除非是经过移民局审批的快速课程，即每年3个学期，4个学期16个月完成2年的课程。

You must have met this eligibility requirement in the six (6) months immediately before the date of making your application. To meet this requirement, you must have completed in no less than 16 calendar months, either:

a single qualification requiring at least two (2) academic years study
or
more than one qualification resulting in a total period of at least two (2) academic years study.
Two (2) academic years study
Two (2) academic years study means the equivalent of two (2) years study enrolled at 100% of a full time load. It is a measure of the amount of study you have completed rather than how long it took you to complete the study.

If you are given credit for prior learning it will reduce the amount of study you have completed.

The department will use the Commonwealth Register of Institutions and Courses for Overseas Students (CRICOS) to determine the standard