To prove that you have competent English you must provide evidence of one of the following:

you have achieved a score of at least 6 for each of the four test components (speaking, reading, listening and writing) of an International English Language Testing System (IELTS) test that has been undertaken in during three years immediately prior to lodging the visa application you have achieved a score of ‘B’ for each of the four test components of an Occupational English Test (OET) that has been undertaken in the three years immediately prior to lodging the visa application  you hold a valid passport from the United Kingdom, the United States of America, Canada, New Zealand or the Republic of Ireland and you are a citizen of that country.