4.3 Fragments, Run-ons, and Comma Splices

Key Takeaways

  • Fragments are incomplete sentences: missing subject, missing verb, or a dependent/relative clause left unattached.
  • Run-ons (fused sentences) jam two independent clauses together with no punctuation and no coordinating conjunction.
  • Comma splices join two independent clauses with only a comma—illegal without FANBOYS (or a stronger mark).
  • Fix strategies include adding the missing piece, attaching a dependent clause to an independent clause, or separating clauses with a period, semicolon, or comma + coordinating conjunction.
  • TEAS "which revision corrects" stems reward the option that removes the error without creating a new one or changing the required meaning.
Last updated: August 2026

Three Errors, One Underlying Map

TEAS sentence-structure items love error identification and revision. Three patterns dominate:

  1. Sentence fragments — not a complete independent thought
  2. Run-on sentences (fused sentences) — two independent clauses smashed together with nothing between them
  3. Comma splices — two independent clauses joined by only a comma

All three are judged against the clause skills from 4.1 and the legal joins from 4.2. If you can mark independent versus dependent and name legal connectors, these errors become easy to spot in academic stems and in sloppy draft notes.

Healthcare documentation fails the same way: a fragment leaves a supervisor unsure what happened; a run-on or splice blurs where one observation ends and the next begins—risky when multiple actions and times matter.

Fragments: Incomplete Sentences

A fragment is punctuated as if it were a sentence but fails the complete-sentence test (subject + predicate + complete thought, with independence).

Common fragment types

TypeClinical-style exampleWhy it fails
Dependent clause aloneBecause the patient reported dizziness.Subordinator leaves thought unfinished
Relative clause aloneWho checked the two identifiers.Relative clause cannot stand alone
-ing / participial phraseChecking the medication label carefully.No finite clause completing who did what as a full sentence (in standard test English)
Prepositional phraseAfter the rapid response arrived.Phrase only; no independent clause
Appositive / detail tailA critical potassium result of 2.8 mEq/L.Noun phrase without a main verb
Missing subjectDocumented the refusal in the chart.Who documented? (Unless clearly imperative in context; TEAS often treats bare past-tense verbs without subjects as errors in "sentence" choices)
Missing verbThe patient in Room 14 with new-onset confusion.No predicate

Healthcare charting fragments to avoid:

  • "When the IV site became erythematous."
  • "Which required discontinuation of the infusion."
  • "After notifying the charge nurse about the change."

Each needs attachment to (or rewriting as) an independent clause.

Fix strategies for fragments

StrategyBeforeAfter
Add independent clauseBecause the patient reported dizziness.Because the patient reported dizziness, the nurse rechecked orthostatic vitals.
Delete subordinator (if meaning allows)Because the patient reported dizziness.The patient reported dizziness.
Attach to previous/next sentenceThe nurse paused. Checking the label carefully.Checking the label carefully, the nurse paused. or The nurse paused and checked the label carefully.
Supply missing subject/verbDocumented the refusal.The nurse documented the refusal.
Turn phrase into full clauseAfter the rapid response arrived.After the rapid response arrived, the team stabilized the patient.

TEAS tip: The best fix keeps the original meaning. Deleting because removes a reason relationship; attaching a main clause preserves it. Choose the revision the stem’s meaning requires.

Run-ons (Fused Sentences)

A run-on joins two independent clauses with no punctuation and no coordinating conjunction.

  • Incorrect: The saturation dropped the nurse applied oxygen.
  • Incorrect: Pain scores remained high the provider was paged.

Readers (and scorers) cannot see the clause boundary. In a chart, that boundary may separate assessment from intervention—exactly what must stay clear.

Fix strategies for run-ons

FixPatternExample
Period (two sentences)IC. IC.The saturation dropped. The nurse applied oxygen.
SemicolonIC; IC.The saturation dropped; the nurse applied oxygen.
Comma + FANBOYSIC, and/but/so… IC.The saturation dropped, so the nurse applied oxygen.
Make one clause dependentSubordinator + DC, IC.When the saturation dropped, the nurse applied oxygen.

Pick the fix that matches logic: so for result, when for time, period for clean separation, semicolon for closely related equals.

Comma Splices

A comma splice uses only a comma between two independent clauses.

  • Incorrect: The culture was positive, antibiotics were started.
  • Incorrect: The patient was NPO after midnight, breakfast was held.

A comma is too weak to join two complete sentences by itself in standard academic English tested on the TEAS.

Fix strategies for comma splices

FixExample
Add FANBOYS after the commaThe culture was positive, so antibiotics were started.
Replace comma with periodThe culture was positive. Antibiotics were started.
Replace comma with semicolonThe culture was positive; antibiotics were started.
Add subordinator to one clauseBecause the culture was positive, antibiotics were started.
Restructure as simple sentence if same subject allowsThe nurse reviewed the culture and started antibiotics per protocol. (only if accurate)

Conjunctive adverb trap: however, therefore, moreover, nevertheless are not FANBOYS. They do not repair a splice when wrapped only in commas.

  • Still a splice: The order was clarified, however, the dose was wrong.
  • Correct: The order was clarified; however, the dose was wrong.

Side-by-Side Error Comparison Table

ErrorDiagnostic testMinimal correct repair example
FragmentCannot stand alone as complete thoughtAttach: Because drainage increased, the nurse measured output.
Run-onTwo ICs with zero separatorSplit or join: Drainage increased. The nurse measured output. / …, so the nurse…
Comma spliceTwo ICs with only a commaAdd conjunction or upgrade mark: Drainage increased, so the nurse measured output.

Same clinical content, three failures, three fixes:

  1. Fragment: "While the transfusion was running." → "While the transfusion was running, the nurse monitored vital signs every 15 minutes."
  2. Run-on: "The transfusion was running the nurse monitored vital signs every 15 minutes." → add comma + and/so or a period/semicolon.
  3. Comma splice: "The transfusion was running, the nurse monitored vital signs every 15 minutes." → same legal joins as the run-on fixes.

TEAS "Which Revision Corrects" Pattern

Many items present a flawed sentence and four rewrites. Use this attack plan:

  1. Diagnose the original error (fragment vs. run-on vs. splice vs. something else).
  2. Eliminate choices that keep the same error (still only a comma between ICs; still a bare because clause).
  3. Eliminate choices that introduce a new error (semicolon before a fragment; comma splice replaced by a run-on; subject-verb disagreement; wrong its/it's).
  4. Prefer the revision that preserves meaning required by the stem (cause, contrast, sequence).
  5. When two are grammatical, pick the clearer structure that matches idea relationships (4.2).

Worked TEAS-style revision

Original (comma splice): The IV site looked swollen, the nurse stopped the infusion.

Choice sketchVerdict
The IV site looked swollen the nurse stopped the infusion.Still wrong (run-on)
The IV site looked swollen; the nurse stopped the infusion.Correct compound with semicolon
Because the IV site looked swollen.Fragment
The IV site looked swollen, so the nurse stopped the infusion.Correct compound with comma + so

Both the semicolon version and the so version can be right; stems usually offer only one fully correct option, or they specify the intended relationship (result favors so).

Original (fragment): Although the wound edges appeared approximated.

Repair directionExample
Complete with ICAlthough the wound edges appeared approximated, serous drainage remained.
Drop subordinatorThe wound edges appeared approximated.

If the stem’s context emphasizes contrast, keep although and add the independent clause rather than deleting the relationship.

Mixed Practice Mindset (Clinical Stems)

Read each as if you were editing a peer’s note before it enters the permanent record:

  • "Patient refused blood draw. Because the vein was not visible." → second sentence is a fragment; attach or rewrite.
  • "The vein was not visible the nurse requested a second staff member." → run-on; fix join.
  • "The vein was not visible, the nurse requested a second staff member." → comma splice; fix join.
  • "When the vein was not visible, the nurse requested a second staff member." → correct complex sentence.

Quick Decision Flow

  1. Find all subject–verb units.
  2. Label each I or D.
  3. If a "sentence" has only D or only a phrase → fragment.
  4. If two I units have no mark between them → run-on.
  5. If two I units have only a comma → comma splice.
  6. Repair with period, semicolon, comma + FANBOYS, or subordination—without orphaning a new fragment.

Master this flow and the TEAS revision items become predictable. You are not hunting for what "sounds sophisticated"; you are enforcing complete thoughts and legal clause boundaries—the same standards that keep nursing and allied-health writing clear, safe, and professional.

Test Your Knowledge

Which option is a sentence fragment?

A
B
C
D
Test Your Knowledge

Which sentence contains a comma splice?

A
B
C
D
Test Your Knowledge

Which revision best corrects the run-on "Pain remained high the provider was notified"?

A
B
C
D
Test Your Knowledge

A TEAS item shows: "Although the IV infiltrated. The nurse discontinued the site." Which revision corrects the error without creating a new one?

A
B
C
D