Last time, we talked about how to find a starting point on a Sentence Correction problem when the starting point doesn’t leap out at you. If you haven’t read that article yet, go ahead and do so.

The first step of the SC process is a First Glance, something that didn’t help out a whole lot on last week’s problem. Let’s try out the First Glance again and see what happens!

This GMATPrep® problem is from the free exams.

* “Often incorrectly referred to as a tidal wave, a tsunami, a seismic sea wave that can reach up to 150 miles per hour in speed and 200 feet high, is caused by underwater earthquakes or volcanic eruptions.

“(A) up to 150 miles per hour in speed and 200 feet high, is

“(B) up to 150 miles per hour in speed and heights of up to 200 feet, is

“(C) speeds of up to 150 miles per hour and 200 feet high, are

“(D) speeds of up to 150 miles per hour and heights of up to 200 feet, is

“(E) speeds of up to 150 miles per hour and as high as 200 feet, are”

What did you do for the First Glance? The glance is designed to give you an upfront hint about one issue that the sentence might be testing before you actually start reading the full sentence. Take a look at the beginning of the underline, including the beginning of all five answer choices.

The split is between up to and speeds of up to. There isn’t an obvious grammar rule here, so the issue is likely to revolve around meaning: do we need to say speeds of or is it enough to say just up to?

Think about this while reading the original sentence. What do you think?

The phrase reach up to could go in several different directions—is it going to say up to 150 miles in length? up to 150 feet high?—so it’s preferable to clarify right up front that the wave is reaching speeds of up to 150 miles per hour.

In addition, the sentence contains parallelism:

can reach up to X [150 miles per hour in speed] and Y [200 feet high]

The portion before the parallelism starts must apply to both the X and Y portions, so the original sentence says:

can reach up to 200 feet high

That might sound kind of clunky and it is: up to and high are redundant.

Okay, answer (A) is incorrect and answer (B) repeats both issues (it neglects to specify speeds of up to 150 and it contains faulty parallelism.).

Check the parallelism in the other choices:

“(C) speeds of up to [150 miles per hour] and [200 feet high]

“(D) [speeds of up to 150 miles per hour] and [heights of up to 200 feet]

“(E) speeds of [up to 150 miles per hour] and [as high as 200 feet]”

In answer (C), the Y portion is the measurement (200 feet), so the X portion should also be the measurement…but it’s nonsensical to say speeds of up to 200 feet high. Likewise, in (E), the Y portion is a prepositional phrase, so it matches the prepositional phrase in the X portion. Now, the sentence says speeds of as high as 200 feet—equally nonsensical.

The only one that makes sense is answer (D): speeds of up to 150 and heights of up to 200.

The correct answer is (D).

You might also have noticed, in the original sentence, that the last underlined word is the verb is. Sentence Correction problems always have at least one difference at the beginning of the underline and at the end, so glance down the end of the choices.

Interesting! Is vs. are. What subject goes with this verb? Here’s the original sentence again:

“Often incorrectly referred to as a tidal wave, a tsunami, a seismic sea wave that can reach up to 150 miles per hour in speed and 200 feet high, is caused by underwater earthquakes or volcanic eruptions.”

The modifiers have been crossed out. The subject is tsunami, a singular noun, so the verb should be the singular is. Answers (C) and (E) are incorrect for this reason.

Key Takeaways: The First Glance in Sentence Correction

(1) Before reading the original sentence, make it a habit to glance at the word or couple of words at the start of the underline and each answer choice. Sometimes, the split will be obvious: an is vs. are split, for example, clearly indicates subject-verb agreement.

(2) Sometimes the split will be less obvious, as with up to vs. speeds of up to. In this case, if the split is fairly easy to remember, just keep the variations in mind as you read the original sentence, so that you can analyze the difference right away. You may see immediately that speeds of up to is more clear, and your knowledge that the sentence is testing this meaning might also alert you to some of the meaning issues introduced by the faulty parallelism.

(3) Making a subject-verb match in the midst of a bunch of modifiers can be tricky. Learn how to strip the modifiers out and take the sentence down to its basic core structure.

* GMATPrep® questions courtesy of the Graduate Management Admissions Council. Usage of this question does not imply endorsement by GMAC.

Want to learn more? Read on to part 3.

Manhattan GMAT

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