IELTS Writing Task 1: Process Diagrams Guide

Structure for Process Diagrams

Unlike charts, process diagrams have a fixed order. Describe the steps sequentially, from the beginning to the end. Use sequencing language to connect each stage clearly.

• Opening: 'The diagram illustrates the process by which...'
• Sequence words: first, initially, next, then, subsequently, after that, finally
• Cyclic processes: 'the cycle then repeats / returns to the beginning'

Using Passive Voice Correctly

Process diagrams almost always require passive voice because the focus is on what happens to materials, not on who does it.

• Active: 'Workers heat the mixture' → Passive: 'The mixture is heated'
• Passive forms: is/are + past participle (is heated, are transported, is converted)
• With agent: 'The water is filtered by a membrane'

Example: First, raw materials are collected and transported to the processing plant, where they are sorted and cleaned before being fed into the main furnace.

Overview for Process Diagrams

State the number of stages and whether the process is linear or cyclical. Mention the input (raw material or starting point) and the output (finished product or end state).

Example: Overall, the process involves six distinct stages, beginning with the extraction of raw materials and ending with the delivery of the finished product to retailers.