Matching headings and sentence completion on one passage

A complete Passage 2 on mangrove forests with six headings to match and seven sentences to complete, solved paragraph by paragraph to show how a Band 8 reader finds main ideas.

Passage 2 in the Academic Reading paper is often a longer text with lettered paragraphs, and matching headings is the task many candidates dread. This lesson works one such passage from start to finish. The headings task and the sentence-completion task use the same text, and the way they support each other is part of what you will learn.

Do the task first. Set a timer for 17 minutes and answer questions 1 to 13 on paper. Then read the walkthrough.

The passage

Mangroves: forests between land and sea

A Walk along a tropical shore in almost any part of the world, and where the sand gives way to soft mud you are likely to meet a forest that stands in the sea. Mangroves are trees and shrubs that grow in the zone between high and low tide, in tropical and subtropical regions across more than a hundred countries; frost kills them, so they are absent from cold coasts. Indonesia has the largest area of mangrove, while the Sundarbans, shared by Bangladesh and India, is the largest single block of mangrove forest. Twice a day the tide floods the trees, and twice a day it drains away. Botanists recognise about eighty species, but they are not a single family. Tolerance of salt water evolved independently in several unrelated groups of plants, and the word “mangrove” describes a way of life rather than a type of tree.

B Life in this habitat is hard, and mangroves have developed a set of remarkable adaptations. Sea water would kill most plants, but some mangroves filter salt out at the roots, while others take it in and get rid of it through their leaves, which can be seen glittering with salt crystals. The mud presents a second problem, because it is soaked with water and contains almost no oxygen. Many species therefore grow special roots called pneumatophores, which rise above the surface like pencils and take in air. A third problem is how to reproduce in a place where a seed would be washed away or buried. In several species the seed begins to grow while it is still attached to the parent tree; the young plant, already equipped with a root, then drops into the water, floats until it reaches suitable mud and takes root.

C The tangle of roots is also a refuge. Beneath the water, the roots offer small animals a place to hide from predators, and the shelter is so effective that mangroves are often described as nurseries. Many species of fish, crabs and prawns spend their early lives among the roots and move to open water or to coral reefs as they grow; fishing communities along tropical coasts depend on the adults that are later caught. Above the water, the branches provide nesting sites for birds, and the mud itself supports snails, worms and other creatures on which larger animals feed. Fallen leaves are broken down by crabs and bacteria and so become food for others further along the chain.

D The same roots and trunks also stand in the way of the sea. They slow moving water, so that mud and sand settle between them and the shore slowly builds up; in some places this may allow the forest to keep pace with rising sea levels. When waves strike a belt of mangroves they lose much of their energy, and after the Indian Ocean tsunami of 2004 several studies suggested that villages sheltered by mangroves suffered less damage than those on open coasts. Researchers urge caution, however. The protection depends largely on the width of the belt and on the height of the wave, and no band of trees can stop the largest waves.

E Mangroves matter for the climate as well. Like other forests, they absorb carbon dioxide as they grow, but they are unusual in where the carbon ends up. Because the mud is waterlogged and contains little oxygen, dead roots and leaves decay very slowly, and the carbon accumulates; most of it lies in the mud beneath the trees rather than in their wood. Per hectare, a mangrove forest can hold several times as much carbon as many forests on dry land, which is why carbon stored in coastal habitats is sometimes called “blue carbon”. When a mangrove forest is cleared and the soil is exposed, some of that store escapes into the air.

F Despite their value, mangroves have been disappearing. It is estimated that around a fifth of the world’s mangrove area was lost between 1980 and 2005. The commonest cause has been the conversion of forest into shrimp ponds, followed by agriculture, building and the cutting of trees for timber and charcoal. In recent years the rate of loss has slowed, partly because of stricter laws, but restoration is not simple. Planting schemes often fail when seedlings are placed on mudflats where mangroves never grew, or where the tides cannot reach them. Experience suggests that the most successful projects first restore the flow of water to the site and then allow the forest to return largely by itself.

The questions

Questions 1 to 6

The passage has six paragraphs, A to F. Choose the correct heading for each paragraph from the list of headings below. Write the correct number, i to viii.

List of headings

i. A hidden store of carbon ii. How mangroves keep pace with rising seas iii. Shelter for the young of other species iv. Trees defined by where they live, not by ancestry v. The use of mangrove timber for building and fuel vi. Loss of forest, and the problem of putting it back vii. Features that allow survival in a harsh setting viii. A defence for people living on the coast

1. Paragraph A
2. Paragraph B
3. Paragraph C
4. Paragraph D
5. Paragraph E
6. Paragraph F

Questions 7 to 13

Complete the sentences below. Choose NO MORE THAN TWO WORDS from the passage for each answer.

7. Mangroves belong to several unrelated plant groups because tolerance of salt water evolved … in each of them.
8. Some mangrove species get rid of salt by passing it out through their …
9. The roots that rise above the mud and take in air are called …
10. In several species, the seed begins to grow while it is still attached to the …
11. The protection that mangroves give against waves depends largely on the … of the belt.
12. Most of the carbon in a mangrove forest lies in the … beneath the trees.
13. The commonest cause of mangrove loss has been the conversion of forest into …

Stop here and do the task before you continue.

The walkthrough

Step 0: Thirty seconds on the instructions

Before the passage, the Band 8 reader looks at the list of headings and reads it once, quickly, circling the content words: carbon, rising seas, young, ancestry, timber, loss, harsh setting, coast. They are not trying to memorise eight headings. They are collecting eight topics to listen for.

They also notice two facts about the task. There are eight headings for six paragraphs, so two headings are distractors. And the sentence-completion questions (7 to 13) are in passage order and use “no more than two words”, so they will come from the same paragraphs they are about to read.

Which task first? Questions 1 to 6 require an overview of every paragraph, while questions 7 to 13 require detail. A Band 8 reader does the headings first. The reading they do for the headings tells them where to find the sentence-completion answers later, so the second task becomes quick.

Band 6 habit: reading the whole passage slowly first, then trying to match headings from memory, or starting with question 7 and never getting an overview.

Step 1: Questions 1 to 6, one paragraph at a time

For each paragraph the Band 8 reader follows the same routine, taking about a minute:

1. Read the first sentence and the last sentence with care.
2. Skim the middle, asking only “what is this paragraph about?”
3. Write a five-word summary in the margin (a mental note is enough).
4. Compare with the headings and look for the one that covers the whole paragraph.
5. Check the one or two nearest headings and ask why each is wrong.

Paragraph A (Question 1).

• First sentence: a forest that stands in the sea, on a tropical shore. Middle: where mangroves grow; how big; the tide. Last sentences: about eighty species, “not a single family”, “a way of life rather than a type of tree”.
• Five-word summary: what counts as a mangrove.
• Answer: iv, Trees defined by where they live, not by ancestry. The paragraph moves from description to its main point: mangroves are grouped by habitat, not by family. “Way of life” = “where they live”; “unrelated groups of plants” = “not by ancestry”.
• No other heading is about the nature of the trees themselves. A Band 6 reader may hesitate because the heading repeats no word from the paragraph. The match is in the idea, not the words.

Paragraph B (Question 2).

• First sentence: “Life in this habitat is hard, and mangroves have developed a set of remarkable adaptations.” That is already the heading. Middle: three problems (salt, mud with no oxygen, reproduction) and three solutions.
• Answer: vii, Features that allow survival in a harsh setting. “Hard” = “harsh”; “adaptations” = “features that allow survival”; “habitat” = “setting”.
• Tempting wrong answer: heading iii (“Shelter for the young of other species”) attracts some readers because the seed “drops into the water” and becomes a “young plant”. That is a detail inside one of the three solutions, and the young plant is the tree’s own. The heading says “young of other species”.

Paragraph C (Question 3).

• First sentence: “The tangle of roots is also a refuge.” Middle: small animals hide, fish, crabs and prawns spend their early lives there, birds nest above. Last sentence: more animals feed on the mud.
• Five-word summary: the roots shelter animals.
• Answer: iii, Shelter for the young of other species. “Refuge” = “shelter”; “spend their early lives” = “the young”; “nurseries” confirms it.
• Tempting wrong answers: none are strong, but a Band 6 reader may be drawn to viii (“A defence for people living on the coast”) because “fishing communities” appear in the middle. That is one clause about people benefiting from the adult fish. The paragraph’s subject is animals, not defence.

Paragraph D (Question 4).

• First sentence: “The same roots and trunks also stand in the way of the sea.” Middle: slowing water so the shore builds up; waves lose energy; villages suffered less damage in 2004. Last sentences: caution, depends on width of belt and height of wave.
• Answer: viii, A defence for people living on the coast. “Stand in the way of the sea” = “defence”; “villages sheltered” = “people living on the coast”.
• The tempting wrong answer is heading ii, “How mangroves keep pace with rising seas”. The paragraph does say that mangroves “may … keep pace with rising sea levels”, but that is one clause inside a sentence about mud settling. Ask the question the Band 8 reader asks: “Does this heading cover the whole paragraph or one sentence?” Heading ii covers about twelve words out of a hundred and fifty. The rest of the paragraph is about waves and villages.

Paragraph E (Question 5).

• First sentence: “Mangroves matter for the climate as well.” Middle: carbon dioxide, slow decay, carbon accumulates in the mud. End: cleared forests release it.
• Answer: i, A hidden store of carbon. “Hidden” fits because most carbon lies “in the mud beneath the trees”, and “store” is repeated by the passage (“that store escapes”).
• Tempting wrong answer: heading vi (loss of forest), because the last sentence says clearing releases carbon. Again one sentence, and the effect, not the main idea.

Paragraph F (Question 6).

• First sentence: “Despite their value, mangroves have been disappearing.” Middle: a fifth lost, causes including timber and charcoal. Last sentences: restoration fails unless water flow is restored.
• Answer: vi, Loss of forest, and the problem of putting it back. Two parts to the heading, and the paragraph has two halves: loss, then restoration. “Restoration is not simple” = “problem of putting it back”.
• Tempting wrong answer: v, “The use of mangrove timber for building and fuel”. The passage does say trees are cut “for timber and charcoal”, and the word timber matches a keyword in the heading. But timber is the fourth cause in a list. Nothing in the paragraph is about using the timber. This is a keyword trap: the heading shares a word with the paragraph, but not its idea.

Summary of the headings strategy. The Band 8 reader never matched a heading to a word. They asked of each heading, “Is this the main idea, or a detail?” Headings ii and v are both details, plausible only to a reader who sees one matching phrase. The whole task took about six minutes.

What a Band 6 reader does at this point. They find a sentence in the paragraph that contains a word from a heading (“timber”, “rising sea levels”, “young plant”), and decide at once. They do not test whether the heading describes the whole paragraph. A second weak habit is spending three minutes on one paragraph instead of marking a best guess and moving on.

Step 2: Questions 7 to 13, sentence completion

The same instructions apply: copy the words exactly, stay within two words, and make the grammar fit. Because the Band 8 reader has just read the whole passage in outline, they already know which paragraph each sentence comes from. Question 7 is paragraph A; 8, 9 and 10 are paragraph B; 11 is paragraph D; 12 is E; 13 is F. Paragraph C has no question, which explains why a heading was the right task for it.

Question 7: “…tolerance of salt water evolved ___ in each of them.”

• Keywords: unrelated plant groups, tolerance of salt water, evolved.
• Deciding sentence: “Tolerance of salt water evolved independently in several unrelated groups of plants.”
• Answer: independently. The gap is an adverb after “evolved”, so the answer type is clear before reading. A Band 6 reader might write “in several unrelated groups”, which is longer than two words and repeats “unrelated groups” from the question stem.

Question 8: “…get rid of salt by passing it out through their ___.”

• Keywords: get rid of salt, passing it out.
• Deciding sentence: “others take it in and get rid of it through their leaves.”
• Answer: leaves. The trap is the earlier phrase “filter salt out at the roots”. That describes the species that exclude salt, not those that get rid of it. The stem says “get rid of”, the same phrase as the passage, so it matches the second half.

Question 9: “The roots that rise above the mud and take in air are called ___.”

• Keywords: roots, rise above, take in air, called. The word called in the stem is also in the passage (“special roots called”).
• Deciding sentence: “special roots called pneumatophores, which rise above the surface like pencils and take in air.”
• Answer: pneumatophores. An unfamiliar word is not a problem here, because it is introduced by “called”. Copy it letter by letter, since a spelling mistake loses the mark. A Band 6 reader may panic at the unfamiliar word and write “like pencils”, which is the description, not the name.

Question 10: “…the seed begins to grow while it is still attached to the ___.”

• Keywords: seed begins to grow, still attached.
• Deciding sentence: “the seed begins to grow while it is still attached to the parent tree.”
• Answer: parent tree. The sentence is almost the same in both texts, which should make you cautious but not suspicious. Copy the complete phrase, “parent tree”. A weaker answer is “root”, which appears in the next clause (“already equipped with a root”) and is a different thing.

Question 11: “…depends largely on the ___ of the belt.”

• Keywords: protection, waves, depends largely.
• Deciding sentence: “The protection depends largely on the width of the belt and on the height of the wave.”
• Answer: width. Notice that the sentence gives two factors, width and height, but the stem says “of the belt”, and height belongs to the wave. A reader who wrote “height” would be matching a word that is near the right sentence but does not fit the grammar of the gap.

Question 12: “Most of the carbon in a mangrove forest lies in the ___ beneath the trees.”

• Keywords: most of the carbon, lies, beneath the trees.
• Deciding sentence: “most of it lies in the mud beneath the trees rather than in their wood.”
• Answer: mud. The tempting wrong answer is “wood”, which comes straight after in the same sentence and is the opposite. The stem uses “beneath the trees” as an anchor, and “wood” is not beneath the trees.

Question 13: “The commonest cause of mangrove loss has been the conversion of forest into ___.”

• Keywords: commonest cause, conversion of forest.
• Deciding sentence: “The commonest cause has been the conversion of forest into shrimp ponds.”
• Answer: shrimp ponds. Two words, within the limit. Writing “shrimp ponds, agriculture, building” breaks the limit. The distractors are the other causes listed in the same sentence: “agriculture”, “building”, “timber and charcoal”. The word commonest tells you the answer is the first item only.

Step 3: Two minutes to check

• Roman numerals written clearly: iv, vii, iii, viii, i, vi (do not write A to F).
• Each completion answer is two words or fewer and copied exactly: independently, pneumatophores.
• Each completion fits the sentence grammatically when you read it aloud in your head.
• Each heading is used only once. Two answers with the same heading is a signal that one of them is wrong.

Answer key

Headings ii and v are the two unused headings. Each matches a clause, not a main idea.

What to take from your own result

• Wrong headings for D or F? You probably chose the heading with a matching phrase (rising sea levels, timber). Before choosing, ask, “How much of the paragraph does this heading cover?”
• Slow on the headings? Do not read the middle of a paragraph in full on the first pass. The first and last sentences carry the main idea in most paragraphs, and the middle is evidence.
• Lost marks in sentence completion? Check whether you answered with a word from the right sentence but the wrong part of it (root for question 10, wood for 12). The answer must fit the stem grammatically and in meaning.

Key points

• Read the list of headings first and collect topic words, then do the headings task before the detail questions: it gives you a map of the passage.
• For each paragraph, read the first and last sentences, state the main idea in about five words, and test each heading against the whole paragraph.
• A heading that matches a single sentence or a single word is usually a distractor. The commonest wrong heading shares a keyword with the paragraph.
• Eight headings for six paragraphs means two will never be used, so do not try to find a home for every heading.
• In sentence completion, find the paragraph from the order of the questions, copy words exactly, respect the word limit and check that the answer fits the grammar of the gap.
• Distractors in completion tasks sit in the same sentence as the answer. Read both sides of the gap in the stem and in the passage.

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