A third of the world's soil is under threat, mostly from farming. Healthy soil grows food, gives us antibiotics, stores carbon and holds water, but farming strips its nutrients and chemical fertilisers damage it further. Fixes range from Pius Floris's bacteria mix to a global soil map, a 'zero net land degradation' target and protected zones.
The summary (14-17) is in B and C, in order. The sentence endings (18-21) move from C to G. The section matching (22-26) uses F twice and jumps between C and G.
Answer key and self-check
Type what you wrote and hit mark. Hide the key first if you haven't done the passage yet. Every question number jumps to its explanation.
Q
Your answer
Answer
Questions 14-17 · Summary completion (ONE WORD ONLY)
How to attack this block: B's two paragraphs give the first three gaps: what healthy soil contains, what it stores for the climate and what it holds against floods. The last gap is the one-word cause named at the start of C's second paragraph.
Question 14
Answer: mineralsSection B, first paragraph, last sentence
Besides microorganisms and plant remains, what does healthy soil contain?
A single gram of healthy soil might contain 100 million bacteria, as well as other microorganisms such as viruses and fungi, living amid decomposing plants and various minerals.
Question says → Passage says
Healthy soil containsA single gram of healthy soil might contain
plant remainsdecomposing plants
Why: 'Plant remains' is 'decomposing plants', and the other item in that pair is 'minerals'. Keep the plural.
The trap: 'Fungi' and 'viruses' are also in the sentence, but they're the 'other microorganisms' the summary has already covered.
Question 15
Answer: carbonSection B, second paragraph, middle
What does soil store that affects the climate?
Soil is also an ally against climate change: as microorganisms within soil digest dead animals and plants, they lock in their carbon content
Question says → Passage says
its function in storingthey lock in their / holding three times the amount of
a significant effect on the climatean ally against climate change
Why: 'Storing' matches 'lock in' and 'holding', and what's held is 'carbon', three times as much as the atmosphere.
The trap: 'Water' is also stored, but that's the next gap and it's about floods, not the climate.
Question 16
Answer: waterSection B, second paragraph, last sentence
What does soil hold that protects buildings and roads?
Soils also store water, preventing flood damage: in the UK, damage to buildings, roads and bridges from floods caused by soil degradation costs £233 million every year.
Question says → Passage says
prevents damage to property and infrastructurepreventing flood damage / damage to buildings, roads and bridges
it holdsSoils also store
Why: Soil stores 'water', which prevents floods. 'Property and infrastructure' sums up buildings, roads and bridges.
The trap: 'Floods' is the obvious word, but soil holds water, not floods. The floods are what happen when it can't.
Question 17
Answer: agricultureSection C, second paragraph, first sentence
What's the main human cause of soil degradation?
Agriculture is by far the biggest problem.
Question says → Passage says
The main factorby far the biggest problem
carried out by humansHumans tend not to return unused parts of harvested crops
Why: 'The main factor' is 'by far the biggest problem', and the problem named is 'agriculture'.
The trap: 'Fertiliser' is a big part of the damage in D, but it's one part of agriculture. The summary asks for the main factor, which the passage names directly.
Sentence endings (A-F)
Questions 18-21
How to attack this block: Each beginning names one thing (crop leftovers, fertiliser, Floris's mix, the zero net idea), so find it and read what it does. Two endings are bait from F: nine countries belongs to the soil map, and the passage never says any idea works better globally.
Question 18
Answer: CSection C, second paragraph, third sentence
What happens to nutrients in unused parts of harvested crops?
Humans tend not to return unused parts of harvested crops directly to the soil to enrich it
Question says → Passage says
may not be put back into the soiltend not to return… directly to the soil
Why: C. 'Tend not to return' becomes 'may not be put back'. In the wild those nutrients go back when plants decay, but farmers don't return them.
The trap: E (damage to the environment) is about fertilisers. Unused crop parts aren't said to cause damage, they just don't get put back.
Question 19
Answer: ESection D, second paragraph
What can synthetic fertilisers do?
Chemical fertilisers can release polluting nitrous oxide into the atmosphere and excess is often washed away with the rain, releasing nitrogen into rivers.
Question says → Passage says
Synthetic fertilisersthis synthetic fertiliser / Chemical fertilisers
damage to different aspects of the environmentinto the atmosphere / into rivers / hurts the soil itself
Why: E. Fertilisers pollute the air, the rivers and the soil itself. Three parts of the environment, so 'different aspects'.
The trap: C (not put back into the soil) belongs to unused crop parts. Fertiliser is the thing that does get put in.
Question 20
Answer: ASection E, fourth and fifth sentences
What can Floris's mixture do for soil?
a good crop of plants emerged that were not just healthy at the surface, but had roots strong enough to pierce dirt as hard as rock
Question says → Passage says
improve the numbera good crop of plants emerged / The few plants that grew in the control plots
quality of plantsnot just healthy at the surface, but had roots strong enough
Why: A. On the treated plots a good crop grew, with healthy plants and strong roots, while the control plots had a few small, weak plants. More plants and better plants.
The trap: F (better at a global level) is wrong: F's first line says measures like this are 'not enough' for the global problem.
Question 21
Answer: DSection G, first paragraph
What could the 'zero net degradation' idea do?
Like the idea of carbon neutrality, it is an easily understood target that can help shape expectations and encourage action.
Question says → Passage says
help governments to be more aware of soil-related issuesways of presenting the problem that bring it home to governments and the wider public
Why: D. Chasek wants a way to 'bring it home to governments', and an easily understood target does that. 'Bring it home' means make people really aware.
The trap: B (nine countries) belongs to the Global Soil Map in F, and F (global level) sounds right for a world target, but the passage never says it's better globally.
Matching information (sections A-G)
Questions 22-26
How to attack this block: F answers twice: it lists ways to collect soil data and explains why a global picture is hard (no agreed classification). The 'before farming' item is the short line about soil in the wild in C, and the motivation is Floris's in E.
Question 22
Answer: ESection E, second sentence
Which section says what motivated one person's soil project?
He came to realise that the best way to ensure his trees flourished was to take care of the soil
Question says → Passage says
one person's motivationHe came to realise that the best way to ensure his trees flourished
a soil-improvement projecthas developed a cocktail of beneficial bacteria, fungi and humus
Why: E. Floris ran a tree-care business and wanted his trees to thrive, so he started looking after the soil. That's his reason for developing the mix.
The trap: G mentions Chasek's proposal, but there's no personal reason behind it. E is the only paragraph about why someone started.
Question 23
Answer: CSection C, second paragraph, second sentence
Which section explains how soil stayed healthy before farming?
In the wild, when plants grow they remove nutrients from the soil, but then when the plants die and decay these nutrients are returned directly to the soil.
Question says → Passage says
before the development of farmingIn the wild
how soil stayed healthythese nutrients are returned directly to the soil
Why: C. 'In the wild' is nature without farming: plants take nutrients and give them back when they decay, so the soil stays fertile.
The trap: C also mentions old farming tricks like rotating crops and leaving fields fallow. Those were already farming, so they're not the 'before farming' part.
Question 24
Answer: FSection F, fifth sentence
Which section gives examples of ways to collect soil data?
can be fed measurements from field surveys, drone surveys, satellite imagery, lab analyses and so on
Question says → Passage says
examples of different ways of collecting informationfield surveys, drone surveys, satellite imagery, lab analyses
Why: F. The Global Soil Map database takes data from field surveys, drones, satellites and labs. That's a list of collection methods.
Question 25
Answer: GSection G, second paragraph
Which section suggests protecting some soils soon?
Several researchers are agitating for the immediate creation of protected zones for endangered soils.
Question says → Passage says
keeping some types of soil safeprotected zones for endangered soils
in the near futureimmediate
Why: G. Researchers want protected zones for endangered soils, created immediately. 'Immediate' covers 'near future'.
The trap: F has a plan with a timeframe (four years), but it's a map, not protection.
Question 26
Answer: FSection F, second to fourth sentences
Which section explains why an overview of soil degradation is hard?
To assess our options on a global scale we first need an accurate picture of what types of soil are out there, and the problems they face. That's not easy. For one thing, there is no agreed international system for classifying soil.
Question says → Passage says
difficult to provide an overviewan accurate picture… That's not easy
a reason whyFor one thing
Why: F again. Getting the global picture is 'not easy', and the reason given is that there's no agreed way of classifying soil.
The trap: People skip F because they've used it for 24. The NB says letters can repeat, and both items come from F.
F again. There's no agreed way to classify soil, so an overview is hard. People skip F because they've already used it.
Words from this passage worth keeping
degradation(B)
the process of getting worse in quality
decomposing(B)
rotting and breaking down
ally(B)
something that helps you in a fight
fertile(C)
able to grow plants well
indiscriminate(D)
done without care or judgement
flourished(E)
grew healthily
agitating for(G)
campaigning strongly for
benchmark(G)
a standard others are measured against
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