IB command term
Explain in IB exams: meaning and how to answer
By Michael Thompson - Head of Teaching Excellence; 15 years as an IB Coordinator
In IB exams, explain means giving a detailed account that includes the reasons or causes behind what you describe. You state what happens and also why or how it happens. The reasoning is where the marks concentrate.
Paraphrased from the command-term definitions in the IB Diploma Programme subject guides (International Baccalaureate Organization).
At a glance
Accounts and analysis
Answer shape: Linked paragraphs that connect parts, causes or differences
What explain asks you to do
Explain combines an account with a mechanism. You say what happens, and you also say why or how it happens. A student who only lists the facts has not yet done what the term asks, because the reasons or causes are the part that makes an answer an explanation.
Build a chain of reasoning
Link your points causally instead of placing facts side by side. Connecting words such as so, because and which leads to show the examiner that each step follows from the one before. A short, well-linked chain shows understanding far better than a paragraph of loosely related statements.
Depth over coverage
One developed causal chain is worth more than several unconnected points. If you have limited time, take one idea and follow it through step by step rather than touching on many ideas without ever saying why any of them matter.
Explain how or explain why?
Questions can pair the term differently, for example explain how versus explain why. Read the wording closely and answer the one that is asked. Then check your draft: if it only says what happens, you have written a describe answer, and the reasons are what separate the two terms.
How explain relates to other command terms
Describe covers what happens; explain adds the reasons behind it. Outline and justify are separate command terms with their own demands, so do not assume they ask for the same thing. Use their own pages to compare them with explain before you practise.
Where it appears
Biology
In biology, treat explain as a prompt to give the mechanism behind a process: name what happens, then link each step to the cause that produces the next one.
Biology tutoringEconomics
In economics, explain calls for linked reasoning. Show how one change leads to another with so, because and which leads to, instead of listing effects.
Economics tutoringPhysics
In physics, explain means saying why something happens, not only what is observed. Connect the observation to its cause step by step.
Physics tutoringPsychology
In psychology, explain asks for the reasons or causes behind a behaviour or finding. Describing it alone is not enough; develop one causal chain in depth.
Psychology tutoringCommon mistakes
- Listing facts side by side without linking them causally.
- Describing what happens and stopping there, which answers describe rather than explain.
- Ignoring whether the question asks explain how or explain why.
- Spreading effort across many brief points instead of developing one causal chain.
Frequently asked questions
- What does explain mean in IB exams?
- It means giving a detailed account that includes the reasons or causes behind what you describe. You show what happens and why or how it happens.
- What is the difference between explain and describe?
- Describe gives the account of what happens. Explain gives the same account and adds the reasons. If your answer has no reasons, it is a description.
- Is it better to cover many points or go deep?
- Depth is better. One developed causal chain is worth more than several unconnected points, because the reasoning is where the marks concentrate.
- How do I make my reasoning show?
- Use causal links such as so, because and which leads to, so each step is clearly connected to the next. This turns a list of facts into an explanation.
Related command terms
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