5.2 Sentence Structure

Clauses and Phrases: The Foundation

Every sentence question hinges on one distinction: clause versus phrase. A clause contains both a subject and a verb. A phrase is a group of related words that lacks a subject-verb pair. "Running down the corridor" is a phrase; "the resident ran" is a clause. Clauses come in two kinds:

• An independent clause expresses a complete thought and can stand alone as a sentence: The monitor beeped.
• A dependent (subordinate) clause has a subject and verb but begins with a subordinating word (because, when, although, if, since) and cannot stand alone: because the monitor beeped.

The TEAS expects you to tell these apart instantly, because the number and type of clauses define the sentence type—and whether the punctuation joining them is legal.

The Four Sentence Types

Notice that a simple sentence can still have a compound subject or verb ("The doctor and nurse arrived") and remain simple—what makes it compound is having two complete clauses, not just two nouns or verbs.

Joining Independent Clauses Correctly

Two independent clauses can be combined in only a few legal ways. Memorizing them prevents the most common run-on errors.

The seven coordinating conjunctions are remembered as FANBOYS: for, and, nor, but, or, yet, so.

Fragments

A sentence fragment looks like a sentence but is missing a subject, a verb, or a complete thought. Three classic fragments and their fixes:

1. No subject: "Charted the patient's intake." → "The nurse charted the patient's intake."
2. No verb: "The technician beside the new analyzer." → "The technician stood beside the new analyzer."
3. A dependent clause alone: "Because the lab was backed up." → "Results were delayed because the lab was backed up."

Run-On Sentences

A run-on improperly joins independent clauses. Two forms appear on the test:

• A fused sentence has no punctuation between clauses: "The patient arrived the nurse took vitals."
• A comma splice uses only a comma: "The patient arrived, the nurse took vitals."

Fix either one with any of the five legal joining methods above—add a period, a semicolon, a comma plus FANBOYS conjunction, or subordinate one clause.

Parallelism

Parallel structure means items in a series, list, or comparison share the same grammatical form. Mixing forms creates an error the TEAS loves to test.

• Not parallel: "The orientation covered charting, medication safety, and how to respond to alarms."
• Parallel: "The orientation covered charting, medication safety, and alarm response."
• Correlative pairs must also match: "The drug is both effective and safe" (adjective/adjective), not "both effective and has few side effects."

Modifiers: Misplaced and Dangling

A modifier must sit next to the word it describes. A misplaced modifier lands next to the wrong word; a dangling modifier describes a word that is not actually in the sentence.

• Misplaced: "The nurse handed a cup to the patient that was full of pills." (Sounds like the patient was full of pills.) → "The nurse handed the patient a cup that was full of pills."
• Dangling: "Walking into the room, the chart was missing." (The chart cannot walk.) → "Walking into the room, the nurse noticed the chart was missing."

Worked Example: Identify and fix the error: "Reviewing the lab results, the diagnosis became clear."

Step 1 – Find the introductory modifier. "Reviewing the lab results" is a participial phrase that needs a doer.

Step 2 – Ask who is reviewing. The first noun after the comma is "the diagnosis," but a diagnosis cannot review anything—this is a dangling modifier.

Step 3 – Insert the real actor. "Reviewing the lab results, the physician recognized the diagnosis."

Answer: The corrected sentence places a logical subject (the physician) right after the introductory phrase so the modifier attaches correctly.