Structural Relationships: Parallel Structure
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An effective sentence operates much like a smoothly functioning classroom: each moving part must act in rhythmic, predictable harmony with the rest. When a teacher instructs students to sit down, to open their books, and to begin reading, the brain intuitively anticipates the rhythm of those commands. If the teacher instead tells students to sit down, to open their books, and that they should begin reading, the sudden structural shift creates cognitive friction. This structural harmony is known as parallel structure. For an educator preparing for the Praxis Core Writing exam, mastering this symmetry is not merely about obeying arbitrary grammar rules; it is the physical physics of writing. It guarantees absolute clarity in lesson plans, rubrics, and formal communications by matching grammatical equivalents with grammatical equivalents.
To build a structurally sound sentence, we rely on a fundamental law of linguistic physics: parallel structure requires using the same grammatical form for two or more corresponding parts of a sentence.
If you begin a list with a noun, every subsequent item must be a noun. If you begin with a verb, every item must be a verb. All elements in a sentence list must share the exact same grammatical form. Consider how this manifests when designing classroom activities.
Parallel Structure Definition: The repetition of a chosen grammatical form within a sentence. By making each compared item or idea in your sentence follow the same grammatical pattern, you create a parallel construction.
The Friction of Gerunds and Infinitives
Two of the most common verb forms tested on the Praxis Core are gerunds (verbs acting as nouns, ending in -ing) and infinitives (the basic form of a verb, typically preceded by to).
- A list comprised entirely of gerunds maintains parallel structure.
- Example: The principal praised the educator for planning engaging lessons, managing the classroom effectively, and grading papers promptly.
- Mixing infinitive verbs with gerunds in a single list creates a parallel structure error.
- Error: The curriculum requires the students to read the text, to analyze the themes, and writing a final essay. (The switch from the infinitive to analyze to the gerund writing breaks the rhythm).
Conjunctions act as the fulcrums of a sentence. Whatever is placed on the left side of the scale must weigh exactly the same—grammatically speaking—as whatever is placed on the right.
Coordinating Conjunctions (The FANBOYS)
Coordinating conjunctions must connect grammatically identical sentence elements to maintain parallel structure. We remember these through the acronym FANBOYS. Coordinating conjunctions include the words "and," "but," "or," "nor," "for," "so," and "yet."
When you use one of these words, check the linguistic weights on either side:
- Linking an adjective and an adverb with a coordinating conjunction breaks parallel structure.
- Linking a noun and a prepositional phrase with a coordinating conjunction breaks parallel structure.
- Error: We evaluate students based on their test scores (noun phrase) and in their daily participation (prepositional phrase).
- Correction: We evaluate students based on their test scores and their daily participation.
Correlative Conjunctions (The Paired Partners)
Correlative conjunctions work as a team. Correlative conjunctions are paired words like "either/or," "neither/nor," "both/and," and "not only/but also."
Because they are inextricably linked, ideas connected by correlative conjunctions must have matching grammatical structures. The Praxis exam frequently tests this by misaligning the words immediately following each half of the pair.
The Golden Rule of Correlative Conjunctions: The grammatical structure following the first part of a correlative conjunction pair must exactly match the grammatical structure following the second part.
- Error: The seminar is not only for new teachers but also veteran educators find it useful.
- Analysis: Not only is followed by a prepositional phrase ("for new teachers"). But also is followed by a full independent clause ("veteran educators find it useful").
- Correction: The seminar is not only for new teachers but also for veteran educators.
When educators evaluate student progress, they must compare apples to apples. The same is true for grammar. Items being compared using the word "than" must have identical grammatical structures, and similarly, items being compared using the word "as" must have identical grammatical structures.
| Comparison Word | Incorrect (Asymmetrical) | Correct (Symmetrical) |
|---|---|---|
| Than | To grade essays takes more time than creating a multiple-choice exam. | Grading essays takes more time than creating a multiple-choice exam. |
| As | His lecture was as engaging as when he leads a lab. | His lecture was as engaging as his lab. |
When dealing with a series of small introductory words—such as to, the, or in—the rule of parallel structure is elegantly simple: All or One. You must either use the word only once at the very beginning of the series, or you must rigorously repeat it before every single item.
Infinitives
- A series of infinitives maintains parallelism by placing the word "to" before the first verb only. (e.g., The student wanted to sit, listen, and learn.)
- A series of infinitives maintains parallelism by repeating the word "to" before every single verb in the series. (e.g., The student wanted to sit, to listen, and to learn.)
Articles (a, an, the)
- An article applying to all members of a series maintains parallelism by appearing only before the first term. (e.g., She gathered the markers, erasers, and rulers.)
- An article applying to all members of a series maintains parallelism by appearing before every single term in the series. (e.g., She gathered the markers, the erasers, and the rulers.)
Prepositions (in, on, at, for, by, etc.)
- A preposition applying to all members of a series maintains parallelism by appearing only before the first term. (e.g., The answers can be found in the textbook, the syllabus, or the online portal.)
- A preposition applying to all members of a series maintains parallelism by appearing before every single term in the series. (e.g., The answers can be found in the textbook, in the syllabus, or in the online portal.)
Mixing these approaches (e.g., placing the article before the first and second items, but dropping it for the third) shatters the parallel structure.
Parallelism applies not just to single words, but to entire units of thought.
Avoiding Structural Shifts in Lists
Lists must remain contained within their designated structural boundaries.
- Shifting from a phrase to a full independent clause within a list creates a parallel structure error.
- Error: The new teacher’s duties include planning lessons, grading tests, and she also has to supervise recess.
- Shifting from a phrase to a full dependent clause within a list creates a parallel structure error.
- Error: The committee voted to approve the $50,000 budget, to hire a new specialist, and that we should extend the school year.
Matching Clauses
When linking larger thoughts, dependent clauses joined by coordinating conjunctions must maintain matching structural formats. To keep the reader oriented, repeating the introductory word of a dependent clause helps ensure clear parallel structure in a series of clauses.
- Clear: The superintendent announced that the schools would close early and that the buses would run on a modified schedule.
Maintaining Voice
Voice dictates whether the subject of the sentence is performing the action (Active) or receiving the action (Passive). Mixing active voice and passive voice within a series of clauses creates a parallel structure error. The sudden shift forces the reader to mentally reorient who is doing what to whom.
- Error (Mixed): The students conducted the science experiment (active), and the results were recorded in their journals (passive).
- Correction (Parallel): The students conducted the science experiment and recorded the results in their journals. (Both active).
You will write countless rubrics, syllabi, and newsletters throughout your career. Bulleted lists are an educator’s best friend for organizing information, but they are unforgiving when it comes to parallel structure.
- Sentences formatted as bulleted lists require each bulleted item to begin with the same part of speech. If Bullet 1 begins with a strong action verb, Bullet 2 and Bullet 3 must also begin with strong action verbs.
- Sentences formatted as bulleted lists require each bulleted item to use the exact same verb tense. Do not mix past, present, and future tenses in a list of ongoing expectations.
Incorrect Syllabus Objectives:
- Analyze historical documents (Present tense verb)
- The writing of persuasive essays (Noun phrase)
- Will present findings to the class (Future tense phrase)
Correct Syllabus Objectives:
- Analyze historical documents
- Write persuasive essays
- Present findings to the class
When approaching a Praxis Core Writing question, your first instinct should be to hunt for the joints of the sentence. Look for the coordinating conjunctions (and, but, or), the correlative pairs (not only/but also), and the comparative markers (than, as). Place your mental finger on the word immediately following these joints. Does the grammar on the left mirror the grammar on the right? If one side holds an infinitive and the other holds a gerund, or if one side holds an adjective and the other holds an adverb, you have found the fault line. Repair the symmetry, and you solve the problem.