Question 190·200 Super-Hard SAT Reading Questions·Standard English Conventions
Researchers recently sequenced the genome of the axolotl—an amphibian capable of regenerating lost _____ light on the genetic basis of tissue regrowth, the project may inform future medical therapies.
Which choice completes the text so that it conforms to the conventions of Standard English?
For SAT punctuation and sentence-boundary questions, first locate the subject and main verb before and after the blank to see how many complete sentences you have. Decide whether the part after the blank should start a new sentence, continue the same sentence, or be set off as extra information. Then eliminate choices that create run-ons (two full sentences with only a comma), fragments (no complete sentence), or illogical modifiers (like an -ing phrase describing the wrong noun), and pick the punctuation that produces clear, complete, and logically structured sentences.
Hints
Find the full ideas
Identify the subject and main verb before the blank, and then the subject and main verb after the blank. Are there two complete thoughts?
Look at 'shedding'
Focus on the phrase starting with shedding light on the genetic basis of tissue regrowth. Which noun is this -ing phrase supposed to describe?
Check for sentence boundaries
Ask yourself: do we need to separate these two ideas into different sentences, or should they stay in one? Eliminate any choice that creates a run-on sentence or makes it sound like the axolotl or its limbs are 'shedding light.'
Match punctuation to structure
Once you decide whether a new sentence should start at the blank, pick the option whose punctuation and capitalization match that structure.
Step-by-step Explanation
See the structure before the blank
Read up to the blank: Researchers recently sequenced the genome of the axolotl—an amphibian capable of regenerating lost limbs _____
This part is already a complete sentence: subject and verb are in Researchers ... sequenced, and the dash phrase an amphibian capable of regenerating lost limbs is extra information about the axolotl.
See the structure after the blank
Now read what comes after the blank: shedding light on the genetic basis of tissue regrowth, the project may inform future medical therapies.
Here, the project may inform future medical therapies is another full clause (subject the project, verb may inform). The phrase shedding light on the genetic basis of tissue regrowth is an -ing phrase that describes the project and is meant to introduce this second clause.
Decide how these parts should connect
Because we have a complete idea before the blank and another complete idea (with an introductory -ing modifier) after it, we need a strong break between them. That strong break should:
- End the first sentence after
limbs - Start a new sentence with
Shedding light ...so that it clearly modifiesthe project
Using only a comma or just running the words together would either create a run-on/comma splice or make it sound like the limbs or the axolotl are 'shedding light,' which is not the intended meaning.
Choose the punctuation that creates two clear sentences
The only choice that ends the first sentence after limbs with a period and begins a new sentence with a capitalized Shedding is limbs. Shedding (Choice C). This correctly produces:
Researchers recently sequenced the genome of the axolotl—an amphibian capable of regenerating lost limbs. Shedding light on the genetic basis of tissue regrowth, the project may inform future medical therapies.