In this example, the existing phrasing, “that flourishes,” makes the remainder of the sentence a relative clause which describes the “vibrant plant life.” However, this choice leaves the sentence without a conjugated verb, making it an ungrammatical fragment. Deleting the underlined portion makes “in unexpected places” a prepositional phrase to describe the “vibrant plant life,” but the sentence is similarly left without a conjugated verb. The choice “flourish” is problematic because of subject-verb disagreement between “vibrant plant life,” which is singular, and “flourish,” which is conjugated to agree with a plural subject. Alternatively, the choice “flourishes” provides the sentence with correctly conjugated subject-verb agreement.

In this example, the choice which includes a comma followed by “and” is incorrect because of the relationship between the two clauses. Because the first clause begins with the subordinating conjunction “because,” it introduces a subordinate clause, which should be set off by a comma when it precedes an independent clause. The inclusion of “and,” however, means that a subordinating conjunction and a coordinating conjunction are used, ungrammatically, in tandem. The choice which includes “then” and no comma is wrong on two counts, as it fails to include a comma to separate the subordinate and independent clause, and the use of “then,” which indicates causation, is redundant with the subordinating conjunction “because,” which has already signaled a causal relationship. The existing phrasing, with no conjunction and no comma, is incorrect because a comma is necessary between an independent clause and a subordinate clause which precedes it. Accordingly, the choice with the comma and no conjunction is these, as there is no redundancy in conjunctions and the comma correctly separates the two clauses.

In this example, the choice which uses a semicolon suggests that both clauses are independent. The first clause, however, cannot stand alone as a complete sentence, as it does not contain a conjugated verb. For a similar reason, the choice which uses a comma and “so” can be discarded. A comma followed by a coordinating conjunction like “so” can only separate independent clauses, and as previously discussed, the first clause is not a full sentence. The choice which uses “because,” a subordinating conjunction, is also incorrect, as it suggests that the second clause is subordinate, but the first clause is not an independent clause, and subordinate clauses cannot appear unless adjacent to independent clauses. The correct choice, then, is the existing phrasing, containing only a comma, as it correctly marks the first clause as a participial clause followed by an independent clause.

In this example, the existing phrasing is ungrammatical, as an appositive clause is followed by a relative clause. In context, “one of the pioneers of bebop style” is an appositive clause which describes who “Charlie Parker” is, and it is followed by “which,” a relative pronoun which marks the remainder of the sentence as a relative clause describing “bebop style.” This choice, however, contains no conjugated verb, making the sentence a fragment. The choice to replace the comma with a semicolon, retaining “which,” is no better, as it suggests the clauses preceding and following the semicolon are independent, which they are not. The choice with no punctuation makes the sentence after “Charlie Parker” appear to stand alone as an independent clause, but this leaves a noun set off by a comma at the beginning of the sentence, for which there is no grammatical justification. The correct choice includes only a comma, as it correctly makes “one of the pioneers of bebop style” into an appositive clause which describes Charlie Parker, while the remainder of the sentence contains a conjugated verb and a description of how he changed jazz “for decades to come.”

In this example, the existing phrasing means that everything which follows “who,” a relative pronoun, should be interpreted as part of the relative clause, as there is no other comma in the sentence to mark the end of the clause. This leaves the sentence erroneously incomplete, as the complementizer “that” suggests that something Americans have “no reason” to do will be introduced after the relative clause. In examining the other choice which doesn’t contain a comma, it appears similarly erroneous, as the relative clause continues through the end of the sentence, never revealing what it is that Americans have “no reason” to do. The choice containing “to have” seems like it might work, as the relative clause is closed with a comma, but in removing the relative clause to examine the remaining sentence, “no reason that Americans to have a hand” remains, and it becomes clear that the complementizer “that” and the infinitive construction “to have” do not function together. The final choice, with “should have,” uses the relative clause correctly, and in removing it, we are left with “no reason that Americans should have a hand,” which is entirely grammatically correct.

In this example, the choice containing “who” and “which” both suggest that the information to follow is part of a relative clause. The comma before “which” suggests that the clause is non-restrictive, while the absence of a comma before “who” suggests that the clause is restrictive. In either case, however, the sentence is left without a conjugated verb, so neither choice is the correct one. The choice “industry has testified” might seem right, as there appears to be a conjugated verb, but there is subject-verb disagreement between “experts,” which is plural, and “has,” which is singular. The existing phrasing, on the other hand, has correct subject-verb agreement, meaning the sentence contains a conjugated verb and is otherwise grammatically correct.

In this example, we are presented with several modifiers across our answer options. The relative clause introduced by “which” must refer to the noun or noun phrase that comes before the comma. Since it is illogical to say that the sun has lead to heated debates, we can eliminate all answers that lead with the relative clause “, which.” This leaves us with only our correct answer: “leading to heated debates over which of these objects deserve​.” Since this option replaces the relative clause “, which” with a participial phrase beginning with “leading,” we are now able to modify the subject or subject containing clause. In this case, this construction is necessary to modify the fact that astronomers discovered the objects, the logical meaning of this sentence.

In this example, we need to identify the order of modifying phrases that correctly expresses a logical meaning. Here, each of our modifiers should be as close as possible to what they’re trying to modify. The logical meaning, in this case, expresses that we used to sit “on top of an old well,” that the old well is described as “in a meadow,” and that the meadow is “behind the corner store. Thus, “on top of an old well in the meadow behind the corner store​” is the correct and logical answer. All other answer choices seem to incorrectly (and illogically) modify either the meadow or the corner store as “on top of an old well.”