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 7.0

The response effectively covers all key stages of the hydroelectric power generation process. You have clearly identified the two distinct phases—daytime electricity generation and nighttime water recycling—and provided a logical summary of the mechanism. The overview is concise and highlights the main features of the diagram well. To reach a higher band, you could further develop the description by explicitly mentioning the role of the 'dam' in relation to the water levels or by providing more precise detail on the transition between the two phases. However, the response is accurate and addresses all parts of the task successfully.

Coherence and Cohesion — Band 7.0

The essay is logically organized, with a clear introduction, an overview, and two body paragraphs detailing the day and night cycles. The progression of ideas is easy to follow, and you have used cohesive devices such as 'At night', 'However', and 'After passing through' to link sentences effectively. Referencing is generally clear, although there is a minor error in the second paragraph where 'so that can be used again' is missing a subject (e.g., 'so that it can be used again'). Overall, the paragraphing is appropriate and contributes to a coherent response.

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 precise and fits the context of the diagram well. There are no significant spelling or word-choice errors that impede communication. To improve further, you could incorporate more varied synonyms for 'water' or 'electricity' to demonstrate a wider range of lexical flexibility, though the current vocabulary is sufficient and accurate for the task.

Grammatical Range and Accuracy — Band 6.5

The response demonstrates a good mix of simple and complex sentence structures. Most sentences are error-free, and your control of tense and subject-verb agreement is generally strong. There is a minor grammatical slip in the second paragraph: 'so that can be used again' is missing the pronoun 'it'. Additionally, 'This day' at the start of the third paragraph is slightly unnatural; 'During the day' would be more precise. Despite these minor issues, the majority of your sentences are accurate, and the grammar does not hinder the clarity of your explanation.

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

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