Hi there - 2nd year meddie at Melbourne here. About that English test, it's basically a pretty stupid test to see if you know a whole bunch of so-called "common" Australian phrases. For example:
Complete the following phrase: "He was as fit as a _______"
It is NOT a multiple choice question which makes it rather tricky if you're not from an English-speaking background. Of course, the answer to the above is 'fiddle'. As for studying for it, there's not really much you can do... If you insist on studying you can google a few phrases but I'm sure they won't help much... Anyways, it's not that important and if you're deemed to require assistance, all you have to do is rock up to some English tutes and there's an interview at the end or something like that... It otherwise doesn't count for anything.
Cheers.