The diagram shows how electricity is generated by a hydroelectric dam.
Sample Response
The diagram illustrates the generation of electricityproduction of power through the use of a hydroelectric dam.
Overall, the process is a linear onea rather complicated one, beginning with stored waterwater 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 pipe called a penstocka 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 force of the flowing water is usedthe 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 then flowssimultaneously empties into the river below the dam. Ultimately, the generatorgenerators in the powerhouse are linked to transmission lines, which are used to transfer electrical energy over long distances.
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.