Hi everyone! Today we're going to tackle those tricky rhetorical purpose questions on the TOEFL reading section. I know many students struggle with these, but have no fear - we're going to share some strategies to help you conquer them once and for all.
The key is learning how to zoom out and see the big picture organization of the paragraph, instead of getting lost in the individual trees (words). Rhetorical purpose questions are really asking "Can you see the forest for the trees?" They want you to understand the overall blueprint and flow of the author's argument. It's like being an architect - you need to be able to step back and analyze the paragraph's structural design and how all the pieces fit together. Once you grasp the overarching organization, these questions become much easier to navigate. In today’s lecture, we teach you to see the paragraph's master plan.
Rhetorical purpose question and answer format
First, let’s look at the format of the rhetorical purpose question. the question typically takes one of these forms:
The author mentions X in order to
Why does the author mention X?
Why does the author include the information X?
(X is a word, phrase, or sentence highlighted in the passage.) The answers are usually phrased in the following terms:
to describe
to illustrate
to explain
to provide evidence
to respond to a seeming counterexample
to eliminate a rival hypothesis
to provide an alternative explanation
to provide a counterexample
Now, about the first four types of answers (to Illustrate, Describe, Explain, Provide Evidence): The correct answers for these choices are about explaining a specific idea or claim in the paragraph. They essentially serve the same purpose, which is to expand on a concept or claim made by the author. For this reason, how they are worded does not matter as they can be rephrased equivalently. For instance, "to illustrate Y" can be rephrased as "to explain Y with an example." The key is identifying Y, what that specific concept or claim is.
This type is the most common style of rhetorical purpose questions. Today, we will show you how to locate clue sentences for these types of rhetorical purpose questions. For the remaining four answer types, you'll need some understanding of how counter-examples or alternative explanations are used in academic passages to either strengthen or weaken a theory. You can find strategies for the latter types in Dr. Byrnes' TOEFL reading course. In fact, the course teaches you strategies for all types of TOEFL reading questions. However, knowing the strategies alone isn't enough. You need to practice the strategies with similar-styled questions. Naturally, to help you master the strategies, Dr. Byrne's TOEFL reading course provides tons of practice questions that require using the same approaches. The course is inexpensive and yours forever. So, even if you need to take a break from studying for the TOEFL, the course will be there for you when you're ready. Please check out Dr. Byrnes' TOEFL reading course syllabus at www.nanheebyrnes.com
Two strategies
Now, the key to tackling rhetorical purpose questions lies in understanding the structure of the passage. TOEFL passages normally move ideas from general to specific. So a general idea that encompasses the whole paragraph, called the topic sentence, usually comes before its support through specific examples, explanations, or evidence. Even within a paragraph, a smaller general idea comes before its support.
Therefore, in most cases, the clue sentence for the rhetorical purpose of X will be the sentence that immediately precedes the highlighted sentence or the topic sentence of the paragraph. So the strategy is first to read the sentence that immediately precedes the highlighted sentence and consider the relationship between them. If the sentence has pronouns, you will have to read the sentences that precede it to understand the antecedents. In other cases, it can be the topic sentence of the paragraph, which most often comes at the beginning.
However, there are exceptions as the clue sentences can come after the highlighted part. This is less common but has been seen on some TOEFL rhetorical purpose questions. This fact highlights the importance of examining the entire paragraph before making your choice.
Today, we will examine rhetorical purpose questions that have clues before the highlighted sentence and also exceptions to these strategies.
Question 1
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| TOEFL Rhetorical purpose |
The sentence says that the 15-speed racing bike is more likely to break down than a tricycle. The sentence is a specific example. So we know it should serve as an example of some general idea. Since this is a very specific example, it could be an idea immediately preceding it. So let's read that and see the underlined one can serve as an example. The sentence before says a more complicated system can break down more easily than a simple system. This general idea fits perfectly to the example we have. So this sentence is the clue and the answer should be the choice that conveys a similar idea. With this, let's consider each choice:
A. To illustrate a general principle about the stability of systems by using an everyday example. This choice is correct. The analogy compares the complex 15-speed bicycle to the simpler tricycle, illustrating the general principle that more complicated systems are more prone to breakdowns or instability than simpler systems. The bicycle/tricycle example serves to clarify this principle using a familiar, everyday scenario.
B. To demonstrate that an understanding of stability in ecosystems can be applied to help understand stability in other situations. While the analogy does demonstrate how principles from ecosystem models can apply more broadly, the main purpose is to illustrate the general principle itself using an example, rather than show the applicability of ecosystem concepts elsewhere. So this choice is not quite accurate.
C. To make a comparison that supports the claim that, in general, stability increases with diversity. This choice is incorrect. The analogy actually supports the opposite claim - that increased complexity (diversity of components) tends to reduce stability, not increase it. The more complex bicycle is less stable than the simple tricycle.
D. To provide an example that contradicts mathematical models of ecosystems. This is incorrect. The analogy reinforces and illustrates the principle derived from the mathematical ecosystem models described earlier, rather than contradicting those models.
Question 2
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| TOEFL Rhetorical purpose |
With that context, the correct option should be talking about the positive feedback among various factors.
Claim = Teotihuacán prosperity is thanks to the positive feedback among various factors relating to obsidian industry
Let's evaluate the options:
A. To explain why manufacturing was the main industry of Teotihuacán - Incorrect
B. To give an example of an industry that took very little time to develop in Teotihuacán - Incorrect
C. To illustrate how several factors influenced each other to make Teotihuacán a powerful and wealthy city - Correct
D. To explain how a successful industry can be a source of wealth and a source of conflict at the same time - Incorrect
Option C is the right choice, as it accurately states that the discussion of "the thriving obsidian operation" serves to illustrate how several factors (obsidian mining/working, trade, population growth, irrigation, religious tourism) positively influenced each other, contributing to Teotihuacán's power and wealth. This aligns with the general idea of positive feedback among those factors mentioned in the preceding sentence.
Question 3
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| TOEFL Rhetorical purpose |
A. To provide support for the idea that habitat destruction would lead to population decline
This is the correct option. Recalling the fate of the Columbian white-tailed deer serves as an example supporting the idea that the habitat destruction from human settlement led to declining deer populations.
B. To compare how two species of deer caused biotic changes in the wilderness environment
Incorrect. The passage does not compare two deer species causing changes.
C. To provide an example of a species of deer that has successfully adapted to human settlement
Incorrect. The Columbian white-tailed deer being given protected status implies it did not adapt successfully.
D. To argue that some deer species must be given a protected status
Incorrect. While it mentions the deer's protected status, the main purpose is to provide an example of population decline, not argue for protected status.
So option A is the correct answer, as recalling the Columbian white-tailed deer's fate provides supporting evidence that habitat destruction from human encroachment led to declining deer populations.
Question 4
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| TOEFL Rhetorical purpose |
The sentence with the underlined phrase states that "Cave art seems to have reached a peak toward the end of the Upper Paleolithic period, when the herds of game were decreasing." It talks about the connection between the cave art popularity and herds decreasing. To understand why the author mentions this connection, find a sentence that talks about the relationship in a general term. A sentence right before says "Perhaps the paintings were inspired by the need to increase the supply of animals." That is, more paintings when food is scarce. The underlined sentence serves as evidence for this sentence, so the correct option should be explaining the idea "the paintings were inspired by the need to increase the supply of animals."
Let's evaluate each choice:
A. To argue that Upper Paleolithic art ceased to include animals when herds of game became scarce. Incorrect. The passage does not argue that the art ceased including animals.
B. To provide support for the idea that the aim of the paintings was to increase the supply of animals for hunting. Correct. The underlined sentence supports the previous statement that the paintings were inspired by a need to increase the animal supply for hunting when herds were decreasing.
C. To emphasize the continued improvement in the quality of cave art throughout the Upper Paleolithic period. Incorrect. The passage does not discuss the quality of the art improving over time.
D. To show the direct connection between the decrease in herds of game and the end of the Upper Paleolithic period. Incorrect. The passage does not make a direct connection between decreased herds and the end of that period itself.
So option B is the correct answer, as the underlined sentence provides supporting evidence for the idea that the aim of the cave paintings was to increase the supply of animals for hunting, especially when animal herds were decreasing.
Question 5
Now let’s consider this question:
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| TOEFL Rhetorical purpose |
The highlighted sentence states "The doorways and windows are made possible by placing over the open spaces thick stone beams that support the weight from above." So it describes how the doorways and windows are made. From the preceding sentences, we know that how the doors and windows are made is an instance of Machu Picchu architecture, and this itself is an instance of stone architecture. There is no explanation about why the author talks about how the doors and windows of stone architecture were built, so we should continue to read after the highlighted sentence.
The sentence right after the highlighted sentence states, "A structural invention had to be made before the physical limitations of stone could be overcome and new architectural forms could be created. That invention was the arch,... " The passage then describes how the arch can solve the physical limitations of stone, becoming one of the most important structural breakthroughs.
So we know that the author is using the description of how doors and windows were made in Machu Picchu, using thick stone beams, as an example of construction methods before the invention of the arch. This sets up a contrast between the limitations of pre-arch stone architecture and the new possibilities that arches introduced.
This context suggests that the correct answer is likely to be the option that relates to illustrating construction methods before the invention of the arch. Let's evaluate each option.
A. To indicate that the combined skeletons and skins of the stone buildings of Machu Picchu were similar to igloos and adobe structures
This option is incorrect. The passage does not mention or compare the construction of Machu Picchu to igloos or adobe structures. It simply describes how the doorways and windows were made using stone lintels or beams.
B. To indicate the different kinds of stones that had to be cut to build Machu Picchu
This option is incorrect. While the passage mentions stone construction at Machu Picchu, it does not provide any details about different kinds of stones used or having to cut various stone types.
C. To provide an illustration of the kind of construction that was required before arches were invented
This is the correct option. The description of using stone lintels/beams to create openings at Machu Picchu illustrates the limitations and requirements of pre-arch stone construction, before the invention of arches allowed for new architectural possibilities, as the passage goes on to explain.
D. To explain how ancient builders reduced the amount of time necessary to construct buildings from stone. This option is incorrect. The passage does not suggest the lintel method at Machu Picchu was used to reduce construction time. It simply describes this as the method required before arched construction was invented.
Question 6
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| TOEFL Rhetorical purpose |
This is the highlighted sentence: "By the early thirteenth century, Western Europeans had also developed and put into use the magnetic compass, which helped when clouds obliterated both the Sun and the stars." Since the sentence has "also," we can infer that the previous sentence must be talking about some other development than the magnetic compass. Since the preceding sentence begins with a pronoun "it," we should read the sentence before that to find the antecedent, which is this: "The astrolabe had long been the primary instrument for navigation, having been introduced in the eleventh century." So the development before the magnetic compass is the astrolabe. It was used for measuring the height of the sun and the fixed stars. In contrast, the magnetic compass was used when the sun and stars were not visible. but This information does not help us understand why the author is talking about the magnetic compass.
So, we should read the sentences after the highlighted one. It begins with another "also." So we know that new maps were the third development. Still, we cannot be sure what the point of the highlighted sentence is, so we should keep reading. Because of "as well," we know that the new norms are still another development. Several subsequent sentences explain what the new norms, or the maritime code or Consulate of the Sea, are. And then finally, it states that "Thus by about 1400 the key elements were in place to enable Europe to begin its seaward adventure." This is the main point: that by the 15th century, all the key elements for the seaward adventure were developed, which are the astrolabe, magnetic compass, new maps, and the maritime code. So we know that the compass was used as one of the elements that allowed maritime travel. The clue sentence comes at the end of the paragraph. When we consider the options, C is precisely what we are looking for, so the answer should be C:To identify one of the technological advances that made sea trade with the East possible