Answering 'Explain' Questions (4–6 Marks)

'Explain' questions are the backbone of the AQA GCSE Geography exam. They appear on every paper and test your ability to show why or how something happens, linking causes to effects in a logical chain. This lesson gives you a clear framework for structuring your explanations and maximising your marks.

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What Does 'Explain' Mean?

When the examiner uses the word "Explain", they want you to give reasons. It is not enough to describe what happens — you must say why it happens and how one thing leads to another.

Describe (what)	Explain (why / how)
"Erosion wears away the cliff."	"Hydraulic action forces water into cracks in the cliff face. The pressure of the trapped water weakens the rock, causing pieces to break away over time."
"The population is growing."	"The birth rate is higher than the death rate because improved healthcare has reduced infant mortality, while cultural factors encourage large families."

Exam Tip: If your answer only contains description (what happens) without reasoning (why/how), you will score in the lower mark band — even if what you have written is accurate.

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Mark Bands for Explain Questions

AQA typically marks 4-mark and 6-mark explain questions using a levels-based mark scheme:

4-Mark Explain Questions

Level	Marks	Descriptor
Level 1	1–2	Basic statements with limited or no explanation. May include some description but little reasoning.
Level 2	3–4	Clear explanations with developed reasoning. Links between causes and effects are made explicit.

6-Mark Explain Questions

Level	Marks	Descriptor
Level 1	1–2	Basic, with isolated points and limited explanation.
Level 2	3–4	Clear, with some developed explanations. Connections between ideas are evident.
Level 3	5–6	Detailed and thorough. Explanations are well-developed with clear chains of reasoning. Specific examples or case studies may be used.

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The PRC Framework: Point – Reason – Consequence

Use the PRC structure to build each paragraph of your explanation:

1. Point — Make a clear geographical statement.
2. Reason — Explain why this happens, using geographical knowledge.
3. Consequence — Show the outcome or result, linking to the next idea.

Example: "Explain how the water cycle transfers water from the oceans to the land." (4 marks)

Water evaporates from the ocean surface due to solar energy heating the water (Point + Reason). The water vapour rises into the atmosphere and cools, condensing to form clouds (Consequence leading to next point). As clouds are carried over land by prevailing winds, the moisture falls as precipitation — rain, snow, sleet or hail (Reason + Consequence). This water then flows over the land surface as surface runoff or infiltrates into the soil, eventually reaching rivers that carry it back to the sea (Final consequence).

This answer scores full marks because every sentence links a cause to an effect, creating a logical chain.

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Connective Words for Explanations

Strong explanations use connective words that signal reasoning. Keep these in your toolkit:

Purpose	Connectives
Giving a reason	because, due to, as a result of, since, owing to
Showing a consequence	therefore, consequently, this means that, as a result, leading to
Adding further detail	furthermore, additionally, moreover, also
Showing a sequence	firstly, then, subsequently, finally
Contrasting	however, whereas, on the other hand, although

Exam Tip: Try to use "because" or "this means that" at least once in every paragraph. These connectives force you to explain rather than describe.

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Structuring a 4-Mark Explain Answer

For a 4-mark question, aim for two developed points using PRC.

Example: "Explain why tropical rainforests have high biodiversity." (4 marks)

Point 1: Tropical rainforests receive high levels of rainfall (over 2,000 mm per year) and consistently high temperatures (around 27°C). These conditions provide abundant water and energy for plant growth, which means there is a large and varied food supply to support many different species.

Point 2: The layered structure of the rainforest — from the forest floor to the emergent layer — creates many different habitats and ecological niches. This means that different species can occupy different layers without directly competing, allowing a greater number of species to coexist.

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Structuring a 6-Mark Explain Answer

For a 6-mark question, aim for three developed points using PRC. Include specific examples or case study details where possible.

Example: "Explain how urbanisation creates challenges in LICs and NEEs." (6 marks)

Point 1 — Housing: Rapid urbanisation means that cities in LICs and NEEs grow faster than housing can be built. This leads to the development of squatter settlements or slums, such as Dharavi in Mumbai, where over 1 million people live in makeshift shelters with limited access to clean water and sanitation. As a result, residents face health risks from waterborne diseases and overcrowding.

Point 2 — Transport: The influx of people into cities creates severe traffic congestion because road infrastructure has not been designed for such large populations. In Lagos, Nigeria, commuters can spend 3–4 hours travelling to work because of gridlocked roads. This reduces economic productivity and contributes to air pollution.

Point 3 — Employment: Many migrants move to cities seeking better-paid jobs, but the formal economy cannot provide enough employment for everyone. Consequently, a large proportion of the urban workforce is employed in the informal sector, where jobs are unregulated, poorly paid and lack security. In Mumbai, it is estimated that 60% of workers are in informal employment.

Exam Tip: For 6-mark explain questions, try to include at least one named example (a place, a statistic, a case study). This moves your answer from Level 2 into Level 3.

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Common Mistakes in Explain Questions

Mistake	Example	How to Fix
Only describing	"There are lots of people in cities."	Add a reason: "...because rural-to-urban migration has increased due to the perception of better jobs and services."
Too vague	"It causes problems."	Be specific: "It causes traffic congestion, which increases journey times and air pollution levels."
No chain of reasoning	"Deforestation causes flooding. It also causes soil erosion."	Link the ideas: "Deforestation removes tree roots that bind the soil, leading to increased soil erosion. Without trees to intercept rainfall, more water reaches the ground surface, which increases surface runoff and the risk of flooding."
Repeating the same point	Writing the same idea in different words	Make sure each paragraph introduces a new cause, factor or consequence

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Process Explanations

Some explain questions ask you to describe and explain a geographical process — such as how a landform is created.

Framework for Process Questions:

1. Starting conditions — What is the situation at the beginning?
2. Process in action — What happens and why?
3. Outcome — What is the result?
4. Continuation — Does the process repeat or develop further?

Example: "Explain the formation of an ox-bow lake." (6 marks)