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Command words in science exams: state, describe, explain and more

What 'state', 'describe', 'explain', 'compare' and 'evaluate' really mean in GCSE Science, with examples of what to write.

Year 9–112 min readUpdated 30 September 2026

Many students lose marks not because they do not know the science, but because they answer the wrong kind of question. The command word tells you what to do. Here are the most common ones.

State / Give / Name

Write a short fact. No explanation needed.

Example: State the unit of force. → newton (N)

Describe

Say what happens. Give the facts or the pattern, in order. You do not need to say why.

Example: Describe the pattern in the graph. → "As temperature increases, the rate of reaction increases."

Explain

Say why or how something happens. Use words such as because, so and this means that. Link each point to the next.

Example: Explain why the rate increases. → "At higher temperature particles move faster, so they collide more often and with more energy, so more collisions are successful."

Compare

Give similarities and/or differences between two things. Each point must mention both things. Use words like whereas or both.

Example: "Plant cells have a cell wall, whereas animal cells do not."

Suggest

Use your science to give a sensible answer to a situation you may not have seen before. There may be more than one right answer.

Calculate

Work out a number. Show your working, give the unit and round sensibly.

Evaluate

Give points for and against, then make a judgement (a conclusion) based on your points.

Justify

Give reasons or evidence to support an answer or a choice.

Quick checklist

In short

Command words tell you what the examiner wants. Learn them, circle them in every question, and match the length of your answer to the marks.

Notes, tests and papers for your exam board

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