How to Read a Process Diagram
- 1Process diagrams show HOW something works or is made — in sequential stages.
- 2There is always a clear START and END to the process.
- 3Count the number of stages before you write.
- 4Identify any materials or substances that are transformed or produced.
- 5Note if it is a linear process (A→B→C→D) or a cycle (returns to the beginning).
Introduction
The diagram illustrates the process by which [product/thing] is [produced/created/recycled].
The diagram shows the [number] stages involved in the [production/manufacturing/treatment] of [topic].
The diagram depicts the life cycle of [organism/material] from [start] to [end].
Sequencing & Process Language
The process begins with / First, [substance] is [action].
In the next/following stage, [it/the material] is [action] by [method].
Once/After [stage X] is complete, [it] is then [action].
This is followed by / Subsequently, [action] takes place.
Finally/In the final stage, [product] is [stored/distributed/completed].
The cycle then repeats / The process returns to the beginning.
Tip: Process diagrams = PASSIVE VOICE. You describe what HAPPENS TO the material, not what it does itself. Write: "The water is filtered" NOT "The water filters."
Passive Voice for Process
Active: Workers heat the material. → Passive: The material is heated.
Active: A machine sorts the items. → Passive: The items are sorted by machine.
Active: They collect the liquid. → Passive: The liquid is collected.
Cycle passive: The eggs are then laid, completing the cycle.
Sample Answer – Band 7
Question
The diagram shows how glass bottles are recycled.
Introduction
The diagram illustrates the six-stage process by which used glass bottles are collected and recycled into new glass products.
Overview
Overall, the recycling process involves collection, transportation, and several stages of treatment before the recycled glass is ultimately used in manufacturing. The process is linear, beginning with consumer disposal and ending with the production of new glass items.
Body
The process begins when consumers deposit used bottles into recycling bins. These are subsequently collected by recycling lorries and transported to a processing facility. At the facility, the glass is first sorted by colour — clear, green, and brown — before being crushed into small fragments known as cullet. The cullet is then cleaned to remove impurities such as labels and metal caps. In the following stage, the cleaned cullet is mixed with raw materials — sand, soda ash, and limestone — and fed into a furnace, where it is heated to over 1,500°C and melted. The molten glass is finally moulded into new bottles or other glass products, which are then distributed for commercial use.
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