All answers on this page include the question number, correct answer and a brief explanation of where to find it in the passage or audio. Use these alongside the original Cambridge IELTS books for the best practice experience.
Test 4 answers with clear explanations
These Cambridge IELTS 21 Test 4 Reading answers explain all 40 questions. Review the evidence for water hyacinth in Kenya, multilingual education, and The Globemakers.
Cambridge IELTS 21 Test 4 Reading answer key
Use these cards for quick marking. Read the passage sections below when an answer needs more review.
1. The problems and benefits created by the spread of the water hyacinth in Kenya
Questions 1 to 132. How could multilingualism benefit India’s poorest schoolchildren?
Questions 14 to 263. The Globemakers: The Curious Story of an Ancient Craft
Questions 27 to 40Passage 1: The problems and benefits created by the spread of the water hyacinth in Kenya
This passage explains how water hyacinth spread through East Africa and Lake Victoria. It covers fishing problems, household smoke and a biogas project that turns the weed into fuel.
Question types: True, False, Not Given, Flow-chart completion, Note completion.
Why: Belgian colonists brought the plant to Rwanda because they liked its leaves and flowers in ponds.
Why: The plant escaped through the Kagera river. The passage does not say fishermen moved it.
Why: The fishing boats now struggle to move through the mass of plants.
Why: The passage links lower income to blocked fishing routes. It does not mention chemicals reducing fish numbers.
Why: Wood and charcoal are both linked to indoor air pollution. The passage does not compare which fuel is worse.
Why: Villagers removed enough water hyacinth to create huge piles on the shore.
Why: Researchers began exploring the plant as a biofuel as early as the 1980s.
Why: The digesters transform a mixture of water hyacinth and cow dung into biogas.
Why: The mixture breaks down during a fermentation process lasting 20 to 30 days.
Also accepted: fermentation.
Why: The clean gas travels through pipes to the place where it is used.
Why: The women spend less time gathering firewood each day.
Why: They can use that time for other work that earns money.
Why: At about $750, the price of a digester is too high for most communities.
Passage 2: How could multilingualism benefit India’s poorest schoolchildren?
This passage examines multilingual education among low-income children in India. It studies teaching languages, school performance and how children's life experience may support learning.
Question types: Matching features, Yes, No, Not Given, Multiple choice.
Why: Delhi has more than 20 million residents. This matches dense population, option I.
Why: Many people recently made Delhi their home. They are new immigrants, option J.
Why: Some people moved from surrounding areas. This matches nearby district, option H.
Why: They moved in search of better jobs. This matches employment opportunities, option B.
Why: The passage calls this the overriding aim of the project. This matches primary objective, option E.
Why: The research compares India with benefits observed in European schools. This matches similar advantages, option F.
Why: More children fail the reading task than the subtraction task. Literacy performance is not better.
Why: Female students are more likely to leave school. Recruitment problems are not mentioned.
Why: The team is testing whether unfamiliar teaching languages cause low learning results.
Why: The researchers will examine teaching practices and pupil-centred methods. They have not rejected this factor.
Why: English instruction may hold back poor children who have little exposure to the language.
Why: Tsimpli says English should not be withdrawn. The phrase means it is too late to remove it completely.
Why: Slum children did not lag behind other urban poor children. Some performed better in literacy and numeracy.
Passage 3: The Globemakers: The Curious Story of an Ancient Craft
This passage reviews Peter Bellerby's book about reviving handmade globes. It follows his technical problems, the history of globe making and the loss of traditional craft skills.
Question types: Matching features, Yes, No, Not Given, Multiple choice.
Why: A simple birthday gift became a difficult decade-long project. This matches challenging task, option G.
Why: The project involved a long series of obstacles. This matches numerous problems, option J.
Why: Buying a suitable globe was not a quick online order. This matches internet purchase, option I.
Why: The available commercial globes were shoddy. This matches inferior makes, option C.
Why: Those cheaper commercial globes were designed for classrooms. This matches educational use, option A.
Why: Bellerby searched places with artisan knowledge. This matches necessary skills, option E.
Why: The writer says people knew the world was spherical from at least the 6th century BCE.
Why: Plato compared Earth to a leather ball. The passage does not say anyone criticised him.
Why: Crates made the first recorded globe. Its accuracy is not described.
Why: Bellerby reasoned that a good-quality globe would not be difficult to find.
Why: He discovered at the end that the paper had stretched and overlapped.
Why: The reviewer connects Bellerby with Behaim's setbacks and Coronelli's ambition.
Why: The book laments the loss of old craft traditions and skilled globe makers.
Why: The reviewer says the book is hardly a blueprint for commercial success.
Your Test 4 review plan
Mark all 40 answers. Group your mistakes by question type. Retake this test after reviewing the matching passage evidence.