GCSE Science Exam Technique: Command Words Explained

Why command words matter

A lot of GCSE students lose marks because they answer the topic instead of the command word. Even if your science is correct, the answer can still miss marks if it is the wrong type of response.

The best way to avoid this is to train yourself to spot what the examiner wants before you start writing.

• Describe means say what happens
• Explain means say why it happens
• Evaluate means judge the idea using evidence or pros and cons

Describe, explain, evaluate — the difference

Describe questions want observations, steps, or features. For example, describe what happens to the heart rate during exercise means you should state the change clearly.

Explain questions need cause and effect. If heart rate increases during exercise, explain would need the reason: muscles need more oxygen and glucose for respiration, so the heart pumps faster to deliver them.

Evaluate questions need a judgement. You may need to weigh up evidence, advantages, disadvantages, or whether a method is valid.

• Describe = what
• Explain = why
• Evaluate = how good or how reliable

Examples of how students lose marks

If the question says explain and a student only describes, the answer usually stays too basic. For example, writing the graph goes up does not explain why it goes up.

If the question says evaluate and a student gives only one advantage, the answer is incomplete because there is no balanced judgement.

• Turning an explain question into a description
• Ignoring evidence in an evaluate answer
• Missing the final judgement sentence in an evaluation

Quick exam tip

Before writing, underline the command word and say to yourself what kind of answer it needs. This takes two seconds and can save several marks.

With practice, your answers will become much more focused.

• Underline the command word
• Match your first sentence to the command word
• Check your final sentence answers the task fully