Sentence Structure

Table of Contents
1. Basic Sentence Components
2. Phrases and Clauses
3. Sentence Types by Structure
4. Sentence Types by Purpose
5. Parallel Structure (Parallelism)
6. Sentence Variety and Effectiveness
7. Modification and Word Order
8. Coordination and Subordination
9. Subject-Verb Agreement in Complex Structures
10. Sentence Combining Techniques
11. Common Sentence Structure Traps
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Sentence structure forms the backbone of clear, effective writing. Understanding how sentences are built helps you construct grammatically correct and varied sentences. This knowledge is essential for crafting well-organized written responses and identifying errors in sentences. Mastering sentence structure involves recognizing different sentence types, understanding the role of clauses and phrases, and applying principles of parallel structure and sentence variety.

1. Basic Sentence Components

1.1 Core Elements

• Subject: The person, place, thing, or idea performing the action or being described. It answers "who" or "what" before the verb.
• Predicate: The part of the sentence containing the verb and providing information about the subject. It tells what the subject does or is.
• Complete Sentence: Must contain both a subject and a predicate and express a complete thought. Example: "The student writes." (Subject: student; Predicate: writes)
• Fragment: An incomplete sentence missing a subject, predicate, or complete thought. Example: "Running to the store." (lacks subject performing the action)

1.2 Types of Verbs

• Action Verbs: Express physical or mental action (run, think, write, analyze)
• Linking Verbs: Connect the subject to a description or state of being (is, are, was, were, become, seem, appear, feel)
• Helping Verbs (Auxiliary Verbs): Work with main verbs to show tense, mood, or voice (has, have, had, will, would, can, could, should, must, may, might)

2. Phrases and Clauses

2.1 Phrases

A phrase is a group of related words that does not contain both a subject and a verb. Phrases cannot stand alone as complete sentences.

• Prepositional Phrase: Begins with a preposition and ends with a noun or pronoun (in the morning, under the table, with great enthusiasm)
• Verb Phrase: Contains a main verb plus helping verbs (has been running, will have completed, should be considered)
• Noun Phrase: Functions as a noun in the sentence (the tall building, my younger sister, that old oak tree)
• Participial Phrase: Begins with a present or past participle and functions as an adjective (running quickly, damaged by the storm, written in haste)
• Infinitive Phrase: Begins with "to" plus a verb (to complete the project, to understand the concept, to write clearly)
• Gerund Phrase: Begins with an -ing verb form that functions as a noun (swimming in the ocean, reading books, writing essays)

2.2 Independent Clauses

An independent clause contains a subject and a verb and expresses a complete thought. It can stand alone as a complete sentence.

• Example: "The teacher explained the concept."
• Example: "Students completed the assignment."
• Can be combined with other independent clauses using coordinating conjunctions or semicolons

2.3 Dependent Clauses (Subordinate Clauses)

A dependent clause contains a subject and a verb but does not express a complete thought. It cannot stand alone and must be attached to an independent clause.

2.3.1 Types of Dependent Clauses

• Adverb Clause: Begins with a subordinating conjunction and modifies a verb, adjective, or adverb (because she studied, when the bell rings, although it was late, if you finish early)
• Adjective Clause (Relative Clause): Begins with a relative pronoun and modifies a noun or pronoun (who lives nearby, that we read, which was interesting, whose book this is)
• Noun Clause: Functions as a noun in the sentence and often begins with words like that, what, whatever, who, whoever, whether (what she said, that he arrived, whoever answers first)

2.3.2 Common Subordinating Conjunctions

Words that introduce dependent clauses and show relationships:

• Time: when, while, before, after, since, until, as soon as
• Cause/Reason: because, since, as
• Condition: if, unless, provided that
• Contrast: although, though, even though, whereas, while

3. Sentence Types by Structure

3.1 Simple Sentence

• Contains one independent clause only
• May have compound subjects or compound verbs
• Example: "The dog barked." (one subject, one verb)
• Example: "The dog and cat played together." (compound subject, one verb)
• Example: "The student read and studied." (one subject, compound verb)

3.2 Compound Sentence

• Contains two or more independent clauses joined together
• No dependent clauses present
• Clauses joined by coordinating conjunction (for, and, nor, but, or, yet, so - remember FANBOYS)
• Clauses can also be joined by a semicolon alone or semicolon with conjunctive adverb
• Example: "The sun set, and the stars appeared."
• Example: "I wanted to go; however, I stayed home."

3.3 Complex Sentence

• Contains one independent clause and at least one dependent clause
• Dependent clause can come before, after, or in the middle of the independent clause
• Example: "Because it rained, the game was canceled." (dependent clause first)
• Example: "The game was canceled because it rained." (independent clause first)
• Example: "The student who studied passed the test." (dependent clause embedded)

3.4 Compound-Complex Sentence

• Contains two or more independent clauses and at least one dependent clause
• Combines features of both compound and complex sentences
• Example: "Although she was tired, she finished her work, and she went home."
• Example: "The book that I borrowed was interesting, but I didn't finish it."

4. Sentence Types by Purpose

4.1 Four Functional Types

• Declarative: Makes a statement and ends with a period. Example: "The library closes at nine."
• Interrogative: Asks a question and ends with a question mark. Example: "When does the library close?"
• Imperative: Gives a command or makes a request. Usually ends with a period. The subject "you" is often implied. Example: "Close the door." (You close the door.)
• Exclamatory: Shows strong emotion and ends with an exclamation point. Example: "What a beautiful day!"

5. Parallel Structure (Parallelism)

5.1 Basic Principle

Parallel structure means using the same grammatical form for items in a list or series. Elements that are equal in function should be equal in form.

5.2 Common Parallel Situations

• Items in a Series: All items should have the same grammatical structure
• Incorrect: "She likes swimming, to run, and biking." (mixed forms)
• Correct: "She likes swimming, running, and biking." (all gerunds)
• Correct: "She likes to swim, to run, and to bike." (all infinitives)

5.3 Parallelism with Coordinating Conjunctions

• Elements joined by and, but, or should be parallel
• Incorrect: "The manager is responsible for hiring staff and to train them."
• Correct: "The manager is responsible for hiring staff and training them."

5.4 Parallelism with Correlative Conjunctions

Correlative conjunctions work in pairs and require parallel structure:

• either...or: "Either study now or fail the test."
• neither...nor: "Neither the teacher nor the students were prepared."
• both...and: "She is both intelligent and hardworking."
• not only...but also: "He not only writes well but also speaks clearly."
• The grammatical structure after each part must match
• Incorrect: "She not only is kind but also generous." (is kind vs. generous - not parallel)
• Correct: "She is not only kind but also generous." (kind vs. generous - both adjectives)

5.5 Parallelism in Comparisons

• When using than or as for comparisons, structures must be parallel
• Incorrect: "Writing is easier than to speak."
• Correct: "Writing is easier than speaking."
• Correct: "To write is easier than to speak."

6. Sentence Variety and Effectiveness

6.1 Varying Sentence Length

• Mix short, medium, and long sentences to maintain reader interest
• Short sentences: Emphasize important points and create impact
• Medium sentences: Provide standard information flow
• Long sentences: Show relationships between complex ideas
• Too many sentences of the same length create monotonous writing

6.2 Varying Sentence Structure

• Alternate between simple, compound, complex, and compound-complex sentences
• Start sentences in different ways (not always subject-verb)
• Begin with adverb: "Carefully, she examined the document."
• Begin with prepositional phrase: "In the morning, we will meet."
• Begin with participial phrase: "Running late, he skipped breakfast."
• Begin with dependent clause: "Although tired, she continued working."

6.3 Avoiding Common Structural Errors

• Run-on Sentence: Two or more independent clauses joined without proper punctuation or conjunction
• Incorrect: "The test was difficult I studied hard." (two independent clauses joined without punctuation)
• Correct: "The test was difficult, but I studied hard." (coordinating conjunction added)
• Correct: "The test was difficult; I studied hard." (semicolon added)
• Comma Splice: Two independent clauses joined with only a comma (no coordinating conjunction)
• Incorrect: "The book is interesting, I recommend it."
• Correct: "The book is interesting, so I recommend it." (coordinating conjunction added)
• Correct: "The book is interesting; I recommend it." (semicolon replaces comma)

7. Modification and Word Order

7.1 Modifier Placement

• Modifier: A word, phrase, or clause that describes or limits another word
• Place modifiers as close as possible to the words they modify
• Misplaced Modifier: Modifier positioned too far from the word it modifies, creating confusion
• Incorrect: "She nearly ate all the cookies." (implies she almost ate but didn't)
• Correct: "She ate nearly all the cookies." (implies she ate most of them)

7.2 Dangling Modifiers

• Dangling Modifier: An introductory phrase that doesn't logically connect to the subject that follows
• Incorrect: "Walking to school, the rain started falling." (the rain wasn't walking)
• Correct: "Walking to school, I felt the rain start falling." (I was walking)
• Incorrect: "After studying all night, the test was easy." (the test didn't study)
• Correct: "After studying all night, I found the test easy." (I studied)

7.3 Squinting Modifiers

• Squinting Modifier: An ambiguous modifier that could modify words on either side of it
• Incorrect: "Students who study regularly often succeed." (does "often" modify studying or succeeding?)
• Correct: "Students who regularly study often succeed." (clarity: study regularly)
• Correct: "Students who study regularly succeed often." (clarity: succeed often)

8. Coordination and Subordination

8.1 Coordination

Coordination joins elements of equal grammatical rank using coordinating conjunctions (FANBOYS).

• Use coordination to join ideas of equal importance
• Example: "The weather was cold, but we went hiking." (two equally important ideas)
• Overuse creates choppy, simplistic writing
• Too much coordination: "I woke up and I ate breakfast and I went to school."

8.2 Subordination

Subordination joins elements of unequal grammatical rank using subordinating conjunctions.

• Use subordination to show relationships between ideas of different importance
• Main idea goes in independent clause; less important idea goes in dependent clause
• Example: "Because the weather was cold, we wore jackets." (reason in dependent clause)
• Example: "We went hiking although the weather was cold." (contrast in dependent clause)
• Creates more sophisticated, varied writing than coordination alone

8.3 Common Trap: Excessive Subordination

• Avoid stringing together too many dependent clauses
• Awkward: "When I arrived at the store that was near the school where my sister works who told me about the sale..."
• Better: Break into multiple sentences or reduce clauses

9. Subject-Verb Agreement in Complex Structures

9.1 Agreement with Compound Subjects

• Joined by "and": Usually takes plural verb. Example: "The teacher and the student are present."
• Exception: Compound subject referring to one person or thing takes singular verb. Example: "Peanut butter and jelly is my favorite sandwich."
• Joined by "or" or "nor": Verb agrees with the closer subject. Example: "Neither the teacher nor the students are ready." Example: "Neither the students nor the teacher is ready."

9.2 Agreement with Intervening Phrases

• Ignore prepositional phrases between subject and verb
• Example: "The box of chocolates is on the table." (subject is "box," not "chocolates")
• Example: "The students in the class are taking notes." (subject is "students")
• Common trap: Don't let intervening words distract from the true subject

9.3 Agreement with Inverted Sentences

• In questions and sentences beginning with "there" or "here," identify the true subject
• Example: "There are many reasons for the decision." (subject is "reasons")
• Example: "Where is the nearest library?" (subject is "library")

10. Sentence Combining Techniques

10.1 Purpose of Sentence Combining

• Eliminate choppiness from too many short sentences
• Show relationships between ideas clearly
• Create more sophisticated, mature writing style
• Reduce unnecessary repetition

10.2 Combining Methods

• Using Coordinating Conjunctions: "The play was long. The play was entertaining." → "The play was long but entertaining."
• Using Subordinating Conjunctions: "She studied hard. She passed the exam." → "Because she studied hard, she passed the exam."
• Using Relative Pronouns: "I met a teacher. The teacher explained the concept." → "I met a teacher who explained the concept."
• Using Participial Phrases: "The student finished the test. The student left the room." → "Finishing the test, the student left the room."
• Using Appositives: "Dr. Smith is a scientist. Dr. Smith won an award." → "Dr. Smith, a scientist, won an award."

11. Common Sentence Structure Traps

11.1 Fragment Traps

• Dependent clause standing alone: "Because I was tired." (needs independent clause)
• Missing subject: "Went to the store." (who went?)
• Missing verb: "The book on the table." (what about the book?)
• -ing verb without helping verb: "The student studying." (should be "is studying" or "was studying")

11.2 Parallel Structure Traps

• Watch for lists mixing different grammatical forms
• Ensure correlative conjunctions (either...or, not only...but also) connect parallel structures
• In comparisons using "than" or "as," both sides must be parallel
• Common error: mixing infinitives and gerunds in a series

11.3 Modifier Placement Traps

• Introductory participial phrases must be followed immediately by the word they modify
• Words like "only," "almost," "nearly," "just" should be placed directly before the word they modify
• Avoid ambiguous placement that could modify multiple words

11.4 Coordination vs. Subordination Confusion

• Don't use coordinating conjunctions when ideas are unequal in importance
• Don't subordinate your main idea - keep it in the independent clause
• Avoid creating false equality between a major point and a minor detail

Mastering sentence structure requires understanding how different components work together to create clear, effective communication. Focus on building sentences with proper subjects and predicates, using phrases and clauses appropriately, maintaining parallel structure, and varying sentence types for emphasis and interest. Recognize common structural errors like fragments, run-ons, and misplaced modifiers to write grammatically sound sentences. These skills form the foundation for all effective written communication and are essential for producing well-constructed written responses.