If you've come across this page in isolation, you're probably scratching your head right about now. Never fear! Just go back to the GRE Text Completions 2 questions and answer them. This page covers the explanations for each of the five questions.
More about the Revised GRE Verbal Section
Question 1
Blank i: Choice B
The first blank (i) is easily answerable even without the blanks ii and iii because that colon is an indicator that a context clue is about to make its appearance! In the first sentence, the colon is acting as an equal sign; the word in the blank (before the colon) is roughly equivalent to the verbiage after the colon. Here, the words "absence of challenge" and "grow weak and flabby" provide a clue to the word that should be in the blank. When your choices are tendentiousness (an intentional bias), complacency (contentment especially when danger lurks) and fractiousness (unruliness or discordance) - think "fracture" – the only word that could indicate a growing weak or flabby would be complacency, which is one of the dangers to which Mills was referring.
Blank ii: Choice D
The next sentences describe two more dangers: partiality and incompleteness. It stands to reason that the following blanks will explain those two dangers. And they do! The context clue that tells us that is the causal word, "Since." There's an explanation coming up. The first blank has to be a negative idea, since it's being defined by the words "even under the best circumstances," which gets rid of Choice F focus on matters close at hand. And since we've already been told that one of the dangers is partiality, Choice D, embrace only a portion of the truth, makes the most sense.
Blank iii: Choice G
The last blank determines whether or not you can read carefully. Since Choice H antithetical (opposed to) uses the prefix "anti-", you may be tempted to choose it since the idea of the sentence is about opposition! But you'd be ignoring the "partiality" danger Mills was warning about. The sentence only works with Choice G , erroneous (wrong; incorrect): opposing ideas are rarely completely erroneous, so it's best to get others' opinions so your thoughts aren't incomplete.
Question 2
Blank i: Choice B
Our first clue as to the meaning of blank i is that word "Ironically" right at the beginning. We know that the sentence will have some sort of opposite meaning somewhere. Blank i indicates that he was "wary" of something, and since the choices for that blank are probity (decency; honesty), extravagance (wastefulness), and disapprobation (moral disapproval), it would be ironic if he'd used so much paper (which is talked about at the end) and hated wastefulness.
Blank ii
This blank is simple – it has to mean "excessive" or "wasteful." The only word that meets the definition is Choice F, profligate.
Question 3
Blank: Choice D
The context clue of "Just as" indicates that the beginning part of the sentence will be equal in meaning or idea to the second part of the sentence. Basically, the sentence shows us that one of the authors' books is used in zoology courses, and another is used in another course. If you weren't carefully reading, you may have been tempted to choose Choice E use! But, since that makes no sense in the blank, the correct choice is D: inform.
Question 4
Blank: Choice E
The key word here is "constraints," because in order to be successful in population growth, the species has to do something with them according to the sentence. Will they enhance with constraints to grow? That doesn't even make sense. Will they replace with constraints to grow? Again, that doesn't make sense. Will they produce with constraints to grow? Unlikely, since that means they'd just hinder themselves. Will they surpass with constraints to grow? They might be able to surpass constraints to grow, but since the word "with" is in the sentence and the meaning revolves around it, it doesn't make sense, either. What about this: Will they reconcile with constraints to grow? Bingo! It's the only word that works correctly in the sentence and it just happens to fit the meaning, too. Species better be able to square up with natural constraints if they want successful population growth.
Question 5
This question is testing your logical reasoning in a big way. A savvy way to go about answering it is by making a little notation on the side in case you get confused trying to figure out which parasites are more dangerous – the older or younger ones - especially with all of the contrasting words in the blanks. In the margin, I'd write "Wills thinks younger parasites are more dangerous" just to keep things straight.
Blank i: Choice B
Here, you need to look to the very end of the paragraph to determine that Wills is talking about a particularly "harmful" parasite. The last sentence states that his theory about "harmful" species isn't proven, so the blank describing the parasites must mean "harmful" or "dangerous". Choice B malignant fits nicely.
Blank ii: Choice E
Blank iii: Choice H
Blank ii works in direct correlation with Blank iii, and together, they must explain Blank i because of the word, "therefore" and must oppose the last half of the paragraph because of the word "yet." Whew! Well, since Mills equates a short amount of time (youth) with danger, then the longer a parasite is around, the less dangerous it becomes: insufficient (not enough) time evolves toward benignity (harmlessness)." If you chose "ample" and "virulence", then you weren't following the logic closely enough, which is where writing a note or two to yourself in the margin comes in handy!

