How exactly are we supposed to write them? You know, those giant 6+ mark questions.
My teacher told me to write them as an essay and not as bullet points or I would lose marks for structure. Is this true?
I'd expand those bulletpoints into sentences - the markschemes specify that the style of writing should be 'appropriate' and show good grammar. If the question is asking you to produce a written account of something, bullets aren't really what they want to get.
fwiw a sentence is a unit of thought. a sentence is something you could speak out loud on a single lungful of air. (do not actually speak during exams for obvious reasons, estimate silently)