Question 22·Easy·Text Structure and Purpose
City planners in Greenville recently launched StreetLeaf, a phone application that lets residents photograph and map individual trees along city streets. Each photo automatically records the tree’s location and species. After six months, more than 2,000 unique trees had been cataloged, allowing planners to identify neighborhoods lacking shade and prioritize them for new plantings. The planning department’s newsletter credits StreetLeaf with speeding up its ongoing effort to expand the city’s tree canopy.
Which choice best states the main purpose of the text?
For main-purpose questions, first quickly summarize the passage in your own words in one simple sentence (for example, 'This paragraph explains X and shows how it helped with Y'). Then scan the choices and immediately cross out any that (1) introduce people, places, or comparisons not in the passage, (2) turn a neutral description into a strong argument or debate, or (3) focus on problems when the passage focuses on solutions. Choose the option that best matches your summary and the overall tone (descriptive, argumentative, narrative, etc.) of the passage.
Hints
Look at the beginning and end
Reread the first and last sentences. What is introduced at the start, and what does the newsletter say about it at the end?
Decide what type of writing this is
Ask yourself: Is the passage mainly making an argument, comparing Greenville to other places, describing difficulties, or explaining something that is working well?
Match your one-sentence summary to a choice
Try to sum up the passage in one short sentence. Then look for the answer choice whose idea is closest to your summary, avoiding choices that add comparisons, strong opinions, or problems that the passage never mentions.
Step-by-step Explanation
Identify the task: main purpose
The question asks for the main purpose of the text. That means you should not focus on small details, but on what the author is mainly doing overall: describing, arguing, comparing, or explaining a problem, etc.
Summarize what the passage actually does
Put the passage into your own words:
- City planners launched an app called StreetLeaf.
- The app lets residents photograph and map trees; each photo records location and species.
- After six months, over 2,000 trees were cataloged.
- This data helped planners find neighborhoods that need more shade and prioritize them.
- A newsletter credits the app with speeding up efforts to expand the tree canopy. Overall, the text is presenting a tool (the app), how it works, and the positive results so far.
Eliminate answer choices that don’t match that summary
Now compare the summary to each choice:
- There is no comparison between Greenville and other cities, so any answer about other cities is off.
- The passage does not argue that tree planting is more important than other services; it just describes one project.
- It also does not focus on problems or obstacles; instead it shows that the app helped. The only answer that matches a description of the new app plus its helpful early results for planners is: D) To describe a new smartphone application for mapping urban trees and the early benefits it has provided to city planners.