Band 7.0 IELTS Writing Task 1 Model Answer

Overall Band Score: 7.0 · Cambridge IELTS 14 · 2026-08-25

IELTS Writing Task 1 question

The diagram below shows how electricity is generated in a hydroelectric power station.

Summarise the information by selecting and reporting the main features, and make comparisons where relevant.

Student answer (Band 7.0)

The diagram shows how electricity is produced in a hydroelectric power station during the day and at night.

Overall, water is stored in a high-level reservoir and is used to generate electricity during the day. At night, the water is pumped back to the high-level reservoir so that can be used again.

This day, water from the river is collected behind a dam in the high-level reservoir. The intake is opened, allowing water to flow down a pipe to the power station. The moving water turns reversible turbines, which operate a generator. The generator produces electricity, which is then sent through power lines to the national grid. After passing through the turbines, the water flows into the low-level reservoir.

At night, the intake is closed. The turbines work in the opposite direction and pump water from the low-level reservoir back to the high-level reservoir. However, the same water can be reused to generate electricity the following day.

AI examiner evaluation

Task Achievement / Task Response — Band 7.5

The response successfully identifies and describes the two main stages of the hydroelectric process: the daytime generation phase and the nighttime pumping phase. You have clearly highlighted the key features, such as the role of the reservoirs, the turbines, and the generator. The overview is concise and effectively captures the cyclical nature of the system. All parts of the prompt are addressed, and the information is presented in a logical, accurate manner that directly reflects the provided diagram. No significant information is omitted, and the comparison between the two operational modes is well-handled.

Coherence and Cohesion — Band 7.5

The response is well-organized with a clear introduction, an overview, and two body paragraphs that logically separate the daytime and nighttime processes. Cohesive devices such as 'At night', 'However', and 'After passing through' are used effectively to guide the reader through the sequence of events. Paragraphing is used appropriately to distinguish between the two distinct phases of the power station's operation. The progression of ideas is smooth, and the referencing (e.g., 'the same water', 'the intake') is clear and consistent throughout the text.

Lexical Resource — Band 6.5

You have used a good range of vocabulary appropriate for a technical description, such as 'reversible turbines', 'high-level reservoir', and 'national grid'. The terminology is accurate and fits the context of the diagram well. While the vocabulary is sufficient and precise, it remains largely functional. To reach a higher band, you could incorporate slightly more sophisticated synonyms or varied collocations to describe the movement of water or the conversion of energy, though the current range is more than adequate for a clear, professional summary.

Grammatical Range and Accuracy — Band 7.0

The writing demonstrates a good command of grammatical structures. You have successfully used a mix of simple and complex sentences, such as 'The intake is opened, allowing water to flow down a pipe to the power station.' There is a minor error in the second paragraph where the subject is missing ('so that can be used again' should be 'so that it can be used again'), but this is a rare slip. The majority of your sentences are error-free, and the punctuation is used correctly to support the clarity of your explanations.

See this exact question answered at other band scores — the same prompt compared across bands.

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