Academic Writing Task 1 · process diagram

A diagram illustrating the process of producing drinking water using solar power: IELTS Writing Task 1 sample answer

An IELTS Writing Task 1 process diagram question with a Band 8 sample answer, the chart redrawn with its data, the vocabulary that lifts the report and how to write about process diagrams.
  • 175 words
  • Process diagrams
  • Academic
  • 20 minutes

The question

The process below shows how drinking water is made using solar power.

Summarise the information by selecting and reporting the main features, and make comparisons where relevant. Write at least 150 words.

How drinking water is produced
  1. 1.Solar energy is captured by a solar panel
  2. 2.Electricity is generated and sent to a converter
  3. 3.The converter powers a pump located in an underground well
  4. 4.Water is pumped from the well into a water tank
  5. 5.Water passes through a filter inside the tank
  6. 6.Filtered drinking water flows through a tap into a moveable container

Chart redrawn by BandLadder from the data in the original IELTS practice task. Many IELTS practice tasks come from the Cambridge IELTS series (Cambridge University Press & Assessment); all rights in the original tasks remain with their owners.

Model answer

Band 8 sample answer

Band 8175 words. Every figure in the answer comes from the chart above.

The provided diagram illustrates the step-by-step process of producing drinking water using solar energy. Overall, the system is a self-contained mechanism that converts sunlight into electricity to extract and purify water from an underground source.

In the first stage of the process, sunlight is captured by a solar panel, which generates electricity. This electrical energy is then transmitted to a converter, which regulates the power supply required to operate a pump submerged in an underground well. Once activated, the pump draws water from the well and transports it upwards through a pipe into a large water tank situated on a wooden platform.

Inside the tank, the water undergoes a purification process as it passes through a water filter. After the filtration stage, the clean drinking water is directed through an outlet pipe. A tap is installed on this pipe, allowing the water to be dispensed into a moveable container as needed. This entire operation functions without the need for external power sources, relying solely on the solar energy collected at the start of the cycle.

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Process diagrams

How to write about process diagrams: tips and vocabulary

  • →Say how many stages there are and where the process starts and ends.
  • →Use the passive and sequencers: first, after this, once, finally.
  • →Keep every stage; a missing step costs task achievement.
  • illustrates

    shows or makes clear by using a diagram

  • subsequently

    happening after something else in a sequence

  • self-contained

    complete and independent of other external systems

  • transmits

    sends energy or signals from one place

  • undergoes

    experiences or is subjected to a process

  • dispensed

    distributed or provided in specific portions

Frequently asked questions

What should the overview say?+

The process relies on solar energy to power a pump that extracts groundwater, which is subsequently filtered and stored for human consumption.

How many words and how long for IELTS Writing Task 1?+

At least 150 words; 170 to 200 is the safe range. Spend about 20 minutes on it and leave 40 for Task 2, which carries twice the marks.

How is IELTS Writing Task 1 scored?+

On four criteria: task achievement, coherence and cohesion, vocabulary, and grammatical range and accuracy. A clear overview of the main features is what most separates Band 6 from Band 7 and above.

How do I describe process diagrams?+

Say how many stages there are and where the process starts and ends. Use the passive and sequencers: first, after this, once, finally. Keep every stage; a missing step costs task achievement.

Keep practising

More process diagrams

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