Faulty comparisons account for a significant number of errors in GMAT Sentence Correction questions.
Comparison questions feature words or phrases indicating similarity or difference. These include words in the comparative or superlative form (greater, less, smaller, more, scarier, friendlier, warmer, colder, better, best); comparison words and phrases (like, unlike, as, as in, just as, that of, those of); and comparison structures (Neither…nor, Either…or).
A comparison can be faulty in two ways:
(1) it is not logical, or
(2) it is not grammatical.
To check for logical errors, examine the meaning of the comparison. Ask yourself: are the things being compared of the same “class” or “type”? Or is the sentence “comparing apples to oranges”?
To check for grammatical errors, examine the structure of the comparison and of the things being compared. Ask yourself: first, does the comparison use a valid idiom and/or overarching structure? Second, are the things being compared in the same grammatical form (parallel)?
The overarching rule here is as follows: Comparisons must be both logical and grammatical.
It is important to note that correcting either type of error always requires fixing the grammar. In other words, you may see a grammar error without a logical error; but you will never see a logical error without an accompanying grammar error.
Often, a comparison will sound okay, but will be missing a few necessary words:
Incorrect: The view from this apartment is not nearly as spectacular as from that mountain lodge.
If you read it quickly, this sentence makes perfect sense: the view from the apartment is being compared to the view from the mountain lodge. But if you look more closely, you’ll see that the sentence actually compares the view from the apartment to the lodge itself.
The basis of comparison needs to be clarified.
Basis of Comparison
If you know the idiomatic expression you can’t compare apples to oranges, then you understand that only similar things can be compared. When checking for logical similarity, make sure that places are compared only to places; qualities only to qualities; parts only to parts; wholes only to wholes; etc.
Grammatical similarity deals with the forms of the words, rather than their meanings.
This part of the process requires an understanding of parallelism. The first element of comparison is structured as a noun + a prepositional phrase (from + another noun). So, the second element of comparison should be structured in the same way: noun (“the view”) + a prepositional phrase (“from that mountain lodge”).
In other words, the two constructions must match:
Parallel structures are not necessarily identical word-for-word. Sometimes, a necessary part of the structure can be replaced by a pronoun, or the order of words can be reversed, or certain words may be implied. The overarching rule is that the comparison must be both grammatically balanced and have logical similarity.
Just like misplaced modifier questions, comparison questions can’t be judged by the ear alone. You have to make sure the sentence actually says what it means to say. Here are the corrected versions of the sentence:
Incorrect:The view from this apartment is not nearly as spectacular as that mountain lodge.
Correct:The view from this apartment is not nearly as spectacular as the one from that mountain lodge.
Correct:The view from this apartment is not nearly as spectacular as the view from that mountain lodge.
Let’s look at another example.
Shakespeare’s plays are different from any other playwrights of his era because they exhibit an exceptional mastery of verse.
Once again, the sentence sounds ok, but it actually compares Shakespeare’s plays to other playwrights. The comparison should be between his plays and the plays of other writers.
This is comparison error:
Incorrect:Shakespeare’s plays vs. any other playwright
Here, you have a modifier plus a noun on one side, and a noun phrase on the other side. Another way to think about it is that you have a person and his creations on one side, and just people on the other side. You need to add the creations to the right-hand side. There are two ways to do this:
Correct:Shakespeare’s plays vs. any other playwright‘s plays
Correct:Shakespeare’s plays vs. those of any other playwright
Note that the order is reversed in the latter correction, yet is still correct: person + creation vs. creation + people. What matters is that both sides contain the same basic elements. They “match” or are “balanced”:
Pronouns can play a big part in correcting comparison errors. Like the phrase “the one from” in the previous example, the phrase “those of” in this example makes it very clear that Shakespeare’s plays are being compared to other playwrights’ plays – not other playwrights.
Incorrect:Shakespeare’s plays are different from any other playwrights of his era because they exhibit an exceptional mastery of verse.
Correct:Shakespeare’s plays are different from those of any other playwrights of his era because they exhibit an exceptional mastery of verse.
Look out for key comparison words and phrases, such as: