Essay · Part 1, compulsory. You're given a topic and two ideas; discuss both, say which is more important, and add a third idea of your own. 140–190 words, neutral or formal register.
Article · Part 2, one of three options. Written for a magazine or website; needs an engaging title, a personal voice, and concrete examples. 140–190 words, semi-formal and lively.
Email / Letter · Part 2, one of three options. Could be formal (to an organisation) or informal (to a friend) - read the task carefully to identify the register needed, and match your tone to the reader throughout. 140–190 words.
Report · Part 2, one of three options. Written for a teacher, manager or committee; describes a situation and makes specific recommendations under clear headings. 140–190 words, neutral and impersonal.
Review · Part 2, one of three options. Written for a magazine, website or teacher; describes something, evaluates it with both praise and reservation, and ends with a clear recommendation. 140–190 words, semi-formal and engaging.