我给移民局写了封信询问这个问题，他们回复说：
WAIVER OF THE IELTS TEST REQUIREMENT - DETAILED INFORMATION:
The following sets out in detail which General Skilled Migration
applicants are exempt from sitting an IELTS test to demonstrate their
English language ability.
* Applicant has passed an Occupational English Test (OET) in relation
to
their nominated occupation - Functional, Vocational, Competent
* Applicant is a native English speaker. A native English speaker is a
person whose first spoken language is English and who is the holder of
a passport of the United Kingdom (UK), Canada, New Zealand, United
States
of America (USA) or the Republic of Ireland - Functional, Vocational,
Competent
* Applicant sat an IELTS test more than 12 months but less than 2 years
before applying for their visa and attained the required level of
English
ability, but the decision maker is satisfied that the applicant's
English
language ability has not deteriorated since sitting this test as they
have
been working full-time in an English speaking country. - Functional,
Vocational, Competent
* Applicant holds NAATI accreditation as an interpreter, conference
interpreter or conference interpreter (Senior). - Functional,
Vocational, Competent
* Applicant holds a degree, diploma or trade qualification from an
academic institution as a result of 2 years full time study where all
instruction has been conducted in English. - Functional
* Applicant has worked in the United Kingdom (UK), Canada, New Zealand,
United States of America (USA) or the Republic of Ireland for 2 years
or more - Functional