在booklet 6： www.immi.gov.au/allforms/booklets/1119.pdf 写的很清楚，Overall 4.5
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Second instalment Visa Application Charge (English language tuition)
Members of your family unit aged 18 years or over included in your application who have been assessed
as not having functional English language skills will be required to pay a second instalment charge (see
form 990i Charges) which entitles them to English language tuition in Australia to achieve functional
English. The full amount of this charge must be paid before a visa can be granted to you. Members of
your family unit who are able to demonstrate functional English ability (eg. obtain an overall band score of
4.5 on the International English Language Testing System (IELTS)) do not have to pay this charge.
Applicants who pay this charge will receive information about the Adult Migrant English Program and
where they can receive their tuition when the visa is granted.