The diagram shows how electricity is generated by a hydroelectric dam.
Sample Response
The diagram illustrates the production of power through the use of a hydroelectric dam.
Overall, the process is a rather complicated one, beginning with water being accumulated in a reservoir and ending with the transmission of power into the power grid via long-distance power lines.
Accumulating water in a reservoir is the first stage in generating hydroelectricity. When power generation occurs, water enters a lengthy tunnel known as a penstock after passing through an intake at the base of the dam. The intake is blocked by a massive gate that stops the flow of water whilst power is not being produced. The water runs down the penstock when the intake is opened, and the pressure it generates is utilised to spin a turbine that is connected to a generator in a location known as the powerhouse. The water that has passed through the turbine simultaneously empties into the river below the dam. Ultimately, the generators in the powerhouse are linked to transmission lines, which are used to transfer electrical energy over long distances.
IELTS Writing Correction
- 1. Use precise terminology Original: production of power Suggested revision: generation of electricity Why it matters: Generation of electricity is the more precise term for the process shown.
- 2. Give an objective overview Original: a rather complicated one Suggested revision: a linear one Why it matters: Complicated is a subjective description, while the diagram presents a clear linear sequence.
- 3. Avoid an unshown stage Original: water being accumulated Suggested revision: stored water Why it matters: The diagram shows water already stored in a reservoir rather than the accumulation process.
- 4. Name the conduit precisely Original: a lengthy tunnel known as a penstock Suggested revision: a pipe called a penstock Why it matters: A penstock is more accurately described here as a pipe carrying water to the turbine.
- 5. Clarify the driving force Original: the pressure it generates is utilised Suggested revision: the force of the flowing water is used Why it matters: This wording makes the connection between the moving water and the turbine clearer.
- 6. Show the sequence Original: simultaneously empties Suggested revision: then flows Why it matters: Then accurately signals that the water enters the river after passing through the turbine.
- 7. Use the singular label Original: generators Suggested revision: generator Why it matters: The diagram labels a single generator in the powerhouse.
- 8. Sentence rewrite Original: The intake is blocked by a massive gate that stops the flow of water whilst power is not being produced. Suggested revision: The intake allows water from the reservoir to enter the penstock. Why it matters: The diagram does not show a massive gate or an inactive operating phase.
- 9. Start with the intake Suggested revision: Begin the sequence with stored reservoir water entering the intake rather than presenting water accumulation as a depicted stage. Why it matters: The diagram begins with the reservoir and intake and does not illustrate how the reservoir fills.
Suggested Rewrites
- production of power generation of electricity
- a rather complicated one a linear one
- water being accumulated stored water
- a lengthy tunnel known as a penstock a pipe called a penstock
- the pressure it generates is utilised the force of the flowing water is used
- simultaneously empties then flows
Why this response received Band 8.0
The response presents the process in a clear, logically ordered sequence and uses precise language to connect the reservoir, intake, penstock, turbine, generator, river, and power lines. Its main limitation is a small amount of unsupported elaboration about a massive gate and periods when power is not being produced. The highest-priority improvement is to keep every detail strictly anchored to what the diagram explicitly shows.
IELTS Writing Criteria Scores
Task Achievement
The overview and detailed sequence accurately cover all principal stages and labelled components of electricity generation.
Avoid adding operational details about a gate or inactive periods that are not explicitly demonstrated in the visual.
Coherence and Cohesion
The process unfolds in a highly logical order, with effective sequencing from water storage to power transmission.
Consider dividing the detailed description into two balanced stage groups to make the progression even easier to scan.
Lexical Resource
A wide and precise technical vocabulary is used naturally, including reservoir, penstock, turbine, generator, and transmission lines.
Prefer strictly diagram-based wording and avoid slightly overstated descriptions such as massive gate when the visual does not label it.
Grammatical Range and Accuracy
Complex passive and relative-clause structures are handled with strong accuracy and consistently clear control.
Refine minor stylistic phrasing, especially the long sentence linking the turbine, generator, and powerhouse.
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IELTS Academic Writing Task 1
The diagram shows how electricity is generated by a hydroelectric dam.
Your response
Write the task yourself, then compare your choices with the annotated response.