A process diagram may show a natural cycle, such as a plant’s life cycle, or a man-made process, such as how a product is manufactured. The same approach works for both: understand the stages, identify the start and finish, and describe the process in the order shown.
Understand the Diagram
Before writing, check:
- Where the process starts and ends
- How many stages it includes
- Whether it is cyclical or has a clear beginning and end
- What materials enter the process
- What each stage does and produces
- How the stages connect
You do not need prior knowledge of the process. Describe what the diagram shows, and avoid adding details that it does not provide.
A Four-Paragraph Structure
Paragraph 1: Introduction
Paraphrase the prompt and identify the process.
Paragraph 2: Overview
Summarize the process as a whole. Mention its main stages, whether it is natural or man-made, and whether it forms a cycle or produces a final result.
Paragraphs 3 and 4: Details
Describe the stages in sequence. You can divide a long process into two groups of stages.
Writing the Introduction and Overview
For an introduction, restate what the diagram illustrates without changing its meaning.
Prompt: The diagram shows how electricity is generated at a power station.
Introduction: The diagram illustrates the stages involved in generating electricity at a power station.
In the overview, describe the broad pattern rather than listing every step. For example:
Overall, the process has several stages, beginning with the preparation of fuel and ending with electricity being sent to consumers.
Include only information supported by the diagram.
Describing the Stages
Explain what happens at each stage, what enters or leaves it, and how it connects to the next stage. Use sequencing phrases when they clarify the order:
- First
- Next
- After this
- At the following stage
- Finally
Many process descriptions use the passive voice because the focus is on what happens to materials:
The mixture is heated before it is transferred to a storage tank.
Use present tense for a process that describes a general procedure. Choose accurate vocabulary and do not force complicated terms you are unsure about.
A Step-by-Step Plan
- Read the prompt and identify what the diagram shows.
- Trace the process from beginning to end.
- Count the stages and note inputs, outputs, and key changes.
- Decide whether the process is cyclical or linear.
- Group the stages into a clear order.
- Write the introduction and overview.
- Describe each stage in sequence.
- Check spelling, punctuation, verb tense, word count, and accuracy against the diagram.
Leave time to review your response. Make sure your overview covers the main features and that every detail comes from the diagram.