Being asked to create your own piece of writing while taking IELTS, TOEFL, CAE or FCE, one may face absolutely different types of exam writing tasks from writing short messages, postcards, emails, a letter in response to a specific situation, describing information that is presented visually, in particular, a graph, chart, diagram, table etc. to writing an article, review or report about a given topic to a target reader, also the writing tasks usually include presenting an opinion, argument, problem-solution or a specific question essay.
All exam writing tasks mentioned above require showing the evidence of knowledge about the styles of writing: formal or informal one.
Below you will see the table demonstrating the main difference of formal vs informal elements of writing styles.
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