You should never repeat yourself or say the same thing twice. Good advice for Praxis Core test takers. In other words, you should avoid doing what the previous sentence just did! In the grammar game, that’s known as redundancy.
Redundancy can take the form of an entire phrase that repeats information provided by an earlier phrase (as in the little joke that opened this paragraph), or it can come down to something as simple as an unnecessary adjective, as in “the tree-filled forest” (by definition, a forest is filled with trees, so pointing this is out is hardly necessary).
Grammar tests like to throw in some redundancy questions now and then because the test-writers know that most people are too concerned with grammar to stop and think about what a sentence actually means. Sentences can be grammatically correct in the sense that it doesn’t break any rules about clauses, agreement, punctuation, or anything like that, but redundancy is still not desirable.
Double negatives are a special type of redundancy that occurs when two words that both indicate the negation of an idea are inserted into a sentence when only one is necessary, as in the sentence “Nobody gave me nothing.” Either “Nobody gave me anything” or “People gave me nothing” would be correct, but you don’t need to use a “negating” word twice.
Which of the following sentences contains an example of redundancy?
(A) The brisk wind swept across the hard surface of the frozen lake.
(B) Nobody had better tell me what I can’t do.
(C) I now see that the right time is now.
(D) Children will act the way that children will act.
(E) None of the above
The correct answer is Choice (E). None of the first four choices actually contains an example of redundancy. Choice (A) isn’t redundant because none of the adjectives are unnecessary: Not all winds are brisk, so adding that detail is fine; not all surfaces are hard, so this detail is fine to add; and not all lakes are frozen, so it’s fine to specify that this one is.
Choice (B) isn’t redundant because, despite the presence of both nobody and can’t, it isn’t actually a double negative: The speaker doesn’t want anyone to tell her that she isn’t able (or permitted) to do something, so “Nobody had better tell me what I can’t do” is exactly what she means.
Choice (C) isn’t redundant because the two uses of “now” don’t refer to the same thing: The right time is now (as opposed to some other time), and the speaker has only just realized this (as opposed to realizing it at some other time).
Choice (D) isn’t redundant because the speaker is presumably pointing out that some situation involving some rambunctious children is out of anyone’s control and that he doesn’t have a good explanation for why children act the way they do — in terms of logic, the sentence is a tautology, but a tautology isn’t the same thing as redundancy in a grammatical sense.