Cambridge IELTS 21 · Test 3 · Task 1 · Task 1

Rain Shadow Desert

Task 1

Question

The diagram below shows how one type of desert, known as a rain-shadow desert, is formed.

Summarise the information by selecting and reporting the main features, and make comparisons where

relevant.

The diagram is a cross-section illustrating the sequence of steps by which a rain-shadow desert

forms inland, next to a coastal mountain range.

The process begins at the sea, where moist winds approach the coast (step 1). As these winds reach

the mountains, they are pushed upwards (step 2), and as they rise they cool down. This causes the

moisture in the air to condense, forming clouds (step 4), which then release rain on the windward

side of the mountains (step 5). This is why the windward side, facing the sea, is wet and supports

plant life.

Once the air has released most of its water, it is now dry and continues to move over the mountain

ridge (step 6). The dry air then descends on the leeward side, the side facing away from the sea,

and reaches the inland areas as dry winds (step 7). Because this air is dry, it produces very little

rain, and over time this creates a rain-shadow desert on the inland side of the mountain range.

Overall, the diagram shows that the same mountain range produces very different conditions on its two

sides: the windward side receives heavy rainfall, while the leeward side, left in the "shadow" of the

mountains, becomes a desert.

The process is described in the correct sequence, following the path of the air from the sea to the

inland desert. Every numbered step is covered, and the key contrast between the two sides of the

mountain is made explicit.

Takeaway: For a process diagram, follow the numbered steps or arrows carefully and end by stating

the outcome of the whole process.

Organised chronologically and then by area (windward vs. leeward). Clear sequence linkers ("The

process begins", "As these winds reach", "Once the air has released", "Overall") guide the reader.

Takeaway: Use first/then/once/finally to match the order of the arrows, and a closing sentence on

the overall result.

Logical and precise terminology: "cross-section", "moist winds", "condense", "windward", "leeward",

"desert", "rain-shadow". Technical words are used accurately and appropriately.

Takeaway: Learn directional and weather vocabulary (*windward, leeward, condense, evaporate, moist

air*) for geophysical processes.

Sequence is handled with accurate passives and present tense ("are pushed upwards", "the moisture

condenses"). Complex conditional and relative structures are error-free.

Takeaway: Present tense + passive is standard for process diagrams; use "once X has happened" to

chain the steps.