IELTS Academic Writing Task 1: Biofuel (Ethanol) Production Process (Band 9 Sample)

The response covers the whole process and, crucially, its overview identifies that this is a cycle — a closed carbon loop — rather than a linear sequence, which is the single most important feature of this diagram. It then reports every key stage in order, from plant growth to combustion and reabsorption.

The report follows the ideal process shape — introduction, overview, then the stages in sequence — and groups them into growing, production and consumption phases. Sequencing language is varied and accurate — "To begin with", "Once mature", "In the production phase", "then", "Finally", "subsequently" — ending by signalling that "the entire cycle begins again".

Process vocabulary is precise and varied — "drawn from the atmosphere", "harvested", "broken down", "cellulose... extracted", "convert those sugars into ethanol", "emit carbon dioxide", "taken up by growing plants" — with accurate verbs rather than a single repeated word.

The present-simple passive is used correctly throughout — "they are harvested", "this cellulose is processed", "microbes are then added", "the ethanol is used" — exactly as a process description requires. A "so that" purpose clause and a non-defining relative clause ("carbon dioxide, which is subsequently taken up by growing plants") add range, and the writing is error-free.