Question 5·200 Super-Hard SAT Reading Questions·Expression of Ideas
Decades of satellite data reveal that the Sahara Desert is slowly expanding southward, encroaching on the Sahel’s fragile grasslands. ______ seasonal greening observed in recent years demonstrates that this vast ecosystem remains responsive to episodic pulses of rainfall.
Which choice completes the text with the most logical transition?
For transition questions, first ignore the choices and read the sentence (or sentences) around the blank to decide the relationship on your own: is it cause/effect, contrast, example, restatement, or similarity? Once you’ve labeled that relationship, quickly classify each answer choice by the kind of connection it usually signals and eliminate any that don’t match. Always check that your chosen transition makes the sentence’s logic clearer, not more confusing, when you read the full sentence back to yourself.
Hints
Compare the tones of the two clauses
Ask yourself: Is the first part of the sentence positive or negative, and is the second part positive or negative? How does that change in tone help you see the relationship?
Identify the logical relationship
Decide whether the second part of the sentence is a result of the first, a similar point, a clarification of it, or a point that complicates or pushes back against it.
Match each choice to a relationship type
Think about what each transition word usually does in sentences: Does it show cause/effect, similarity, or restatement? Eliminate any option whose usual function does not fit the relationship you identified.
Step-by-step Explanation
Understand the meaning of each part of the sentence
Read the sentence around the blank:
- First part: "Decades of satellite data reveal that the Sahara Desert is slowly expanding southward, encroaching on the Sahel’s fragile grasslands." This is a negative, worrying trend.
- Second part: "seasonal greening observed in recent years demonstrates that this vast ecosystem remains responsive to episodic pulses of rainfall." This is a positive, hopeful point that shows the ecosystem still responds to rain.
So the two parts are not saying the same thing; they are in tension with each other: bad news vs. some good news.
Decide what kind of relationship connects the two ideas
Ask: How does the second idea relate to the first?
- Is the greening a result of the desert expanding? No, the sentence does not say that.
- Is the greening similar to the desert expansion? No, they are opposite in tone (loss vs. recovery).
- Is the greening simply a restatement of the expansion? No, it introduces a new, different idea.
- Instead, the second part complicates or balances the first: even though the desert is expanding, the land can still green up with rainfall. That is a contrast or an unexpected twist relative to the first clause.
Match each answer choice to its type of transition
Now, classify each option by the relationship it usually signals:
- "Consequently," usually means as a result (cause → effect).
- "Similarly," usually means in the same way (similarity).
- "In other words," usually means to say this another way (restatement or clarification).
- The remaining choice signals a contrast or an unexpected turn between two ideas.
Since we decided the sentence needs a contrast transition, we should select the option that introduces a contrasting idea.
Pick the transition that shows contrast
The only option that introduces an idea that goes against or qualifies the negative trend described earlier is "Nevertheless,", which shows that despite the Sahara’s expansion, there is still seasonal greening that proves the ecosystem remains responsive to rainfall. So the correct answer is B) Nevertheless,.