7.2 Sentence Structure, Run-Ons, Fragments, Comma Splices & Modifiers

Alberta Police Cognitive Ability Test APCAT

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1 Chapter 1: APCAT Exam Overview & Alberta Police Recruitment

1.1 Exam Identity, Eligibility & Alberta Police Hiring Process 1.2 Exam Structure, Timing, Scoring & Five Cognitive Domains 1.3 Strategic Test-Taking Tactics, Time Management & Eliminating Traps

2 Chapter 2: Judgment — Incident Prioritization & Situational Decision-Making

2.1 Life Safety Hierarchy & Emergency Action Prioritization 2.2 Officer Safety Principles, Tactical Awareness & Risk Assessment 2.3 De-Escalation, Tactical Communication & Persons in Crisis

3 Chapter 3: Judgment — Ethics, Discretion & Alberta Policing Standards

3.1 Ethical Dilemmas, Integrity, Conflicts of Interest & Police Discretion 3.2 Procedural Justice, Bias-Free Policing & Charter Rights Awareness 3.3 Use of Force Continuum (Alberta Provincial Use of Force Framework) & Proportionality

4 Chapter 4: Problem Analysis — Mathematics & Numerical Reasoning

4.1 Multi-Step Arithmetic, Metric Conversions & Speed-Distance-Time 4.2 Resource Allocation, Budgeting, Percentage Calculations & Crime Rates 4.3 Ratios, Proportions & Unit Conversions in Police Operations

5 Chapter 5: Problem Analysis — Deductive Logic, Sequences & Critical Thinking

5.1 Deductive Reasoning, Syllogisms & Conditional Logic Rules 5.2 Logical Sequences, Number Patterns & Alphanumeric Series 5.3 Information Ordering, Timelines & Incident Chronology

6 Chapter 6: Observation Skills — Visual Evidence & Investigative Comparison

6.1 Alphanumeric String Verification & Multi-Witness Statement Discrepancies 6.2 Diagram, Map Reading & Crime Scene Spatial Analysis 6.3 Physical Description Accuracy, Facial Features & Vehicle Identification 6.4 Matching Diagrams to Written Descriptions & Person-in-Disguise Comparison

7 Chapter 7: Written Communication — Grammar, Syntax & Police Report Mechanics

7.1 Objective vs. Subjective Language & Professional Police Report Writing 7.2 Sentence Structure, Run-Ons, Fragments, Comma Splices & Modifiers 7.3 Punctuation, Capitalization, Quotation Rules & Possessives 7.4 Police Vocabulary, Spelling & Commonly Confused Homophones 7.5 Official Item Formats: Spelling, Closest-in-Meaning Vocabulary & "Least Grammatically Correct"

8 Chapter 8: Learning & Memory Recall — The Pretest Study Booklet

8.1 Pretest Study Booklet Overview & 30-Minute Memorization Strategy 8.2 Memorizing Suspect Profiles, Wanted Bulletins & Vehicle Descriptions 8.3 Memorizing 10-Codes, Offence Codes & Municipal Policy Procedures 8.4 Form Memorization, CAD Log Recall & Post-Retention Recall Strategies

7.2 Sentence Structure, Run-Ons, Fragments, Comma Splices & Modifiers

Key Takeaways Explain This Topic AI

An independent clause contains a subject and a finite predicate and expresses a complete thought, whereas a dependent clause begins with a subordinating conjunction and cannot stand alone.

Sentence fragments omit a subject, an active finite verb, or a complete thought, whereas run-on sentences and comma splices improperly join independent clauses without necessary punctuation or conjunctions.

Comma splices must be repaired via one of three standard methods: a period split into two sentences, a comma paired with a coordinating conjunction (FANBOYS), or a semicolon.

Dangling and misplaced modifiers create absurd or misleading factual statements by positioning descriptive clauses away from their logical subjects in occurrence narratives.

Subject-verb agreement requires singular subjects to pair with singular verbs across intervening prepositional phrases and indefinite pronouns (each, neither, either, everyone), while pronoun antecedents must remain unambiguous.

Last updated: August 2026

7.2 Sentence Structure, Run-Ons, Fragments, Comma Splices & Modifiers

Executive Summary: The Alberta Police Cognitive Ability Test (APCAT) directly tests your ability to detect and correct structural syntax defects under strict time limits. In legal and investigative reporting, ambiguous sentence structure, misplaced modifiers, and comma splices are not merely stylistic flaws—they distort the chronological sequence of events, confuse lines of criminal liability, and provide defense counsel with avenues to challenge officer credibility. This section teaches the syntactic mechanics required to identify and resolve every major sentence error tested on the APCAT.

Clause Anatomy: Independent vs. Dependent Clauses

Mastery of sentence mechanics begins with understanding the difference between independent and dependent clauses. ┌─────────────────────────────────────────────────────────────────────────┐

│ CLAUSE STRUCTURE & TAXONOMY │
├──────────────────────────┬──────────────────────────────────────────────┤
│ INDEPENDENT CLAUSE │ DEPENDENT (SUBORDINATE) CLAUSE │
├──────────────────────────┼──────────────────────────────────────────────┤
│ • Contains a Subject and │ • Contains a Subject and a Verb, BUT begins │
│ a Finite Predicate │ with a Subordinating Conjunction │
│ • Expresses a complete, │ • Cannot stand alone as a sentence; leaves │
│ standalone thought │ the thought incomplete │
│ • Example: │ • Example: │
│ "Constable Zhao │ "Because the suspect discarded the │
│ seized the weapon." │ weapon in the alley..." │
└──────────────────────────┴──────────────────────────────────────────────┘
Common Subordinating Conjunctions

When any of the following words introduce a clause, they turn it into a dependent clause requiring an attached independent clause: after, although, as, because, before, even though, if, since, so that, unless, until, when, whenever, where, whereas, while .

Identifying and Correcting Sentence Fragments

A sentence fragment is an incomplete grammatical unit masquerading as a complete sentence. Fragments typically result from one of three structural errors: ┌─────────────────────────────────────────────────────────────────────────┐

│ THE THREE FRAGMENT CATEGORIES │
├──────────────────────────┬──────────────────────────────────────────────┤
│ FRAGMENT TYPE │ FLAWED DRAFT VS. CORRECTED SYNTAX │
├──────────────────────────┼──────────────────────────────────────────────┤
│ 1. Missing Subject │ Flawed: "Observed the suspect running west." │
│ │ Fixed: "Constable Ross observed the suspect │
│ │ running west." │
├──────────────────────────┼──────────────────────────────────────────────┤
│ 2. Participle Trap │ Flawed: "The suspect running across the │
│ (Missing Finite Verb) │ four-lane intersection." │
│ │ Fixed: "The suspect was running across the │
│ │ four-lane intersection." │
├──────────────────────────┼──────────────────────────────────────────────┤
│ 3. Standalone Dependent │ Flawed: "Although the perimeter was sealed." │
│ Clause │ Fixed: "Although the perimeter was sealed, │
│ │ the suspect escaped through a vent." │
└──────────────────────────┴──────────────────────────────────────────────┘

Grammar Anchor: An -ing verb (present participle) cannot serve as the main verb of a sentence on its own without an auxiliary helping verb ( was, were, is, had been ).

Run-On Sentences & Comma Splices: The Three Repair Protocols

A run-on sentence occurs when two or more independent clauses are joined together without appropriate punctuation or coordinating conjunctions.

Fused Sentence: Two independent clauses jammed together with zero punctuation: "The suspect fled on foot Constable Lee initiated a foot pursuit."

Comma Splice: Two independent clauses joined by only a comma without a coordinating conjunction: "The suspect fled on foot, Constable Lee initiated a foot pursuit." THE THREE REPAIR PROTOCOLS

┌──────────────────────────────────────┐
│ COMMA SPLICE / RUN-ON DETECTED │
│ [Clause 1] , [Clause 2] │
└──────────────────┬───────────────────┘
│
┌──────────────────────────┼──────────────────────────┐
▼ ▼ ▼
┌──────────────────┐ ┌──────────────────┐ ┌──────────────────┐
│ PROTOCOL 1: │ │ PROTOCOL 2: │ │ PROTOCOL 3: │
│ PERIOD SPLIT │ │ COMMA + FANBOYS │ │ SEMICOLON JOIN │
│ [Clause 1]. │ │ [Clause 1], and │ │ [Clause 1]; │
│ [Clause 2]. │ │ [Clause 2]. │ │ [Clause 2]. │
└──────────────────┘ └──────────────────┘ └──────────────────┘
The Coordinating Conjunctions (FANBOYS)

The only seven coordinating conjunctions that can join two independent clauses when preceded by a comma are:

F or, A nd, N or, B ut, O r, Y et, S o
Semicolons with Conjunctive Adverbs

When connecting independent clauses with conjunctive adverbs ( however, furthermore, consequently, therefore, nevertheless ), a semicolon must precede the adverb, and a comma must follow it:

"The witness identified the vehicle; however, she could not describe the driver."

Broken (Comma Splice / Run-On) Repaired Sentence Structure

The officer arrived on scene, the door was unlocked. Period Split: The officer arrived on scene. The door was unlocked.

The suspect dropped the bag, he jumped the fence. Comma + FANBOYS: The suspect dropped the bag, and he jumped the fence.

The breath sample was invalid, the test was repeated. Semicolon: The breath sample was invalid; the test was repeated.

The driver was speeding, however he stayed in his lane. Semicolon + Adverb: The driver was speeding; however, he stayed in his lane.

Dangling and Misplaced Modifiers in Incident Reporting

A modifier is a word, phrase, or clause that describes or adds detail to another word. Under the Rule of Proximity , a modifying phrase must be placed immediately adjacent to the exact noun it logically describes. ┌─────────────────────────────────────────────────────────────────────────┐

│ MODIFIER ERROR CLASSIFICATION │
├──────────────────────────┬──────────────────────────────────────────────┤
│ DANGLING MODIFIER │ The modifying phrase lacks a logical subject │
│ │ in the main clause, making the introductory │
│ │ action attach to the wrong noun. │
│ │ Example: "Running down the alley, the gun │
│ │ was dropped by the suspect." │
│ │ (Literally states that the gun was running) │
├──────────────────────────┼──────────────────────────────────────────────┤
│ MISPLACED MODIFIER │ The modifier is separated from its target │
│ │ noun, causing comical or factual confusion. │
│ │ Example: "The officer interviewed the witness│
│ │ in the patrol car who saw the robbery." │
│ │ (States the patrol car saw the robbery) │
└──────────────────────────┴──────────────────────────────────────────────┘
Correcting Modifier Errors

Dangling Fix: Supply the true acting subject immediately following the introductory comma:

Flawed: "Searching the dark basement, a hidden shotgun was discovered by Constable Patel."
Correct: "Searching the dark basement, Constable Patel discovered a hidden shotgun behind the furnace."

Misplaced Fix: Move the modifying clause directly next to the noun it describes:

Flawed: "The detective seized a hunting knife from the suspect with a six-inch blade."
Correct: "The detective seized a hunting knife with a six-inch blade from the suspect."
Subject-Verb Agreement Under Complex Syntax

A verb must always agree in grammatical number (singular or plural) with its true grammatical subject, not with nearby intervening nouns or prepositional phrases. ┌─────────────────────────────────────────────────────────────────────────┐

│ SUBJECT-VERB AGREEMENT RULES │
├──────────────────────────┬──────────────────────────────────────────────┤
│ 1. Intervening Phrases │ A box [singular subject] of illegal 9mm │
│ Do Not Alter Number │ handguns [prepositional phrase] WAS seized │
│ │ (not 'were seized'). │
├──────────────────────────┼──────────────────────────────────────────────┤
│ 2. Singular Indefinite │ Each, either, neither, everyone, everybody, │
│ Pronouns │ someone, nobody, anyone take SINGULAR verbs. │
│ │ Example: "Each of the four suspects WAS │
│ │ interviewed separately." │
├──────────────────────────┼──────────────────────────────────────────────┤
│ 3. Compound Subjects │ • Joined by 'AND' = Plural verb │
│ (And vs. Or / Nor) │ ("The constable and the sergeant ARE...") │
│ │ • Joined by 'OR / NOR' = Agrees with the │
│ │ CLOSEST subject: │
│ │ "Neither the sergeant nor the constables │
│ │ WERE in the station." │
├──────────────────────────┼──────────────────────────────────────────────┤
│ 4. Collective Nouns │ In Canadian formal legal English, collective │
│ │ nouns (the jury, the service, the crowd) │
│ │ take SINGULAR verbs when acting as a unit. │
│ │ Example: "The Calgary Police Service IS │
│ │ investigating the collision." │
└──────────────────────────┴──────────────────────────────────────────────┘
Pronoun-Antecedent Agreement & Ambiguous References

A pronoun must agree in number and gender with its antecedent (the specific noun it replaces). Furthermore, a pronoun must point to only one unmistakable antecedent .

Ambiguous Pronoun Traps

In incident reporting, using pronouns when two people of the same gender are involved creates dangerous narrative ambiguity:

Ambiguous: "When Constable Davis confronted the driver, he pulled out his cell phone and dropped his wallet."

Question: Who pulled out the phone? Who dropped the wallet? Constable Davis or the driver?

Court-Ready Revision: "When Constable Davis confronted the driver, the driver pulled out a cell phone and dropped the driver's wallet."