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IELTS is not hard. It is like grade 6 english. But you are expected to get 75/100 in each section. (Since it is 7/9) Listening is a joke... Reading is 'pick the right answer'. The writing component test a lot on your general knowledge, grammer and structure. 1 of the topic I got was 'Is globalization a positive or negative process. Why?' The other I got was 'Should international students be allowed to work during their studies? If so, why?'.Speaking test on your ability to converse with people on general topic such as favourite store, sports, clothes, etc...
Cost 370 per attempt and available almost every week. Wait 2 weeks for results.
OET is the alternative to IELTS in Aus. It test alot on your ability to understand medical terminology. The listening is challenging, but do-able if you listen to handovers often enough. The reading is 'fill in the blanks'. Writing gives you a scenario and requires you to write a refer letter of 250 words +/- 10% with the required information. Just identify the crucial points and write them down within the word limits and time frame and you will be fine. Speaking is role playing.
Cost 580 and available about once every month. Wait 4 weeks for results.