6.1 Sentence Structure: Fragments & Run-ons

Clauses: The Building Blocks of Every Sentence

About 25 percent of the GED Reasoning Through Language Arts (RLA) test measures language conventions — grammar, usage, and sentence structure. On the real exam these are drop-down editing items: a passage contains a highlighted word or phrase, and you choose the best of four options from a menu. To edit confidently, you must first understand the clause, the basic unit of every sentence.

An independent clause (main clause) has a subject and a verb and expresses a complete thought, so it can stand alone: The committee approved the plan. A dependent clause (subordinate clause) also has a subject and a verb, but it opens with a subordinating conjunction or a relative pronoun that leaves the idea unfinished: Although the committee approved the plan — the reader is still waiting. A dependent clause cannot stand alone; joining it to an independent clause completes the thought.

Common subordinating conjunctions include because, although, since, when, while, if, unless, after, before, until, and whereas. Common relative pronouns are who, whom, whose, which, and that. Spotting one of these words tells you the clause is dependent and cannot be punctuated as a full sentence on its own.

The Four Sentence Types

• Simple: one independent clause. The rain fell.
• Compound: two independent clauses joined correctly. The rain fell, and the streets flooded.
• Complex: one independent clause plus at least one dependent clause. Because the rain fell, the streets flooded.
• Compound-complex: two independent clauses plus a dependent clause. Because the rain fell, the streets flooded, and traffic stopped.

Recognizing the type helps you choose punctuation and dodge the two errors the GED tests most often: fragments and run-ons.

Fixing Sentence Fragments

A fragment is an incomplete sentence punctuated as though it were whole. Fragments arise three ways: (1) a missing subject (Ran to the store.), (2) a missing verb (The manager in the corner office.), or (3) a dependent clause standing alone (Because the deadline was tight.). Fix a fragment by adding the missing part or by attaching it to a neighboring independent clause.

Before: We canceled the picnic. Because a storm was coming. After: We canceled the picnic because a storm was coming.

The dependent clause because a storm was coming now attaches to the independent clause, producing one complete complex sentence. On the GED, a highlighted fragment usually needs to be combined with the sentence before or after it.

Run-ons and Comma Splices

A run-on (fused sentence) jams two independent clauses together with no punctuation: She finished her homework she went to bed. A comma splice joins two independent clauses with only a comma: She finished her homework, she went to bed. Both are errors, and both share the same five repairs:

The seven coordinating conjunctions spell FANBOYS: for, and, nor, but, or, yet, so. Place a comma before a FANBOYS conjunction only when it joins two independent clauses — not when it joins a clause to a short phrase (She sang and danced needs no comma, because danced has no subject).

Conjunctive Adverbs Are Not Conjunctions

Words such as however, therefore, moreover, consequently, and nevertheless are conjunctive adverbs, not coordinating conjunctions. They cannot join two independent clauses with only a comma — doing so creates a comma splice. Use a semicolon before and a comma after: The plan was expensive; however, the board approved it. This is a favorite GED trap because however feels as if it should work the way but does, but but is a true conjunction and however is not.

Coordination vs. Subordination

Coordination links two ideas of equal weight with a comma + FANBOYS or a semicolon. Subordination makes one idea depend on another and signals a relationship — cause, contrast, or time: Because the weather was terrible, we canceled the event. On sentence-combining items, the strongest answer usually shows the logical relationship clearly; a precise because or although often beats a vague and. Avoid choices that pile on conjunctions (Although it rained, but we still went) — use one connector, not two.

Parallel Structure

Parallel structure means that items in a series or comparison take the same grammatical form — all nouns, all gerunds (the -ing form), or all infinitives (to + verb). A shift in form breaks parallelism.

Not parallel: She enjoys reading, writing, and to run. Parallel: She enjoys reading, writing, and running.

Common trap: the GED loves to bury the faulty item at the end of a list, where the first two matching forms lull you into approving a mismatched third. Read every item in a series back against the same lead verb before you choose.

A Quick Editing Checklist

When a drop-down highlights a full clause, run this three-step scan:

1. Count the subject-verb pairs. Two complete thoughts with no proper joiner signal a run-on (no punctuation) or a comma splice (comma only).
2. Look for a lone subordinator. A clause that opens with because, although, since, or when and ends in a period is a fragment; attach it to a neighboring sentence.
3. Check every series. If the sentence lists actions or traits, confirm all items share one grammatical form so the list stays parallel.

Applying this checklist in order catches the great majority of sentence-structure errors before you even read the answer choices.

Combining Sentences to Show a Relationship

Many GED items ask you to combine two short sentences into one. The best answer keeps every fact and makes the logical link explicit without creating a run-on.

Sentence 1: The weather was terrible. Sentence 2: We decided to cancel the outdoor event. Weak: The weather was terrible, and we decided to cancel the outdoor event. (vague and) Strong: Because the weather was terrible, we canceled the outdoor event.

Subordinating with because names the cause, so it beats a loose and. Reject any choice that drops a fact, repeats the subject awkwardly, or fuses the clauses with no punctuation.

The Compound-Predicate Comma Trap

A single subject can perform two actions joined by and. That is a compound predicate, not two clauses, so it takes no comma before and.

Wrong: The clerk filed the report, and answered the phone. Right: The clerk filed the report and answered the phone.

Add the comma only when a second subject appears: The clerk filed the report, and she answered the phone. Ask, "Does a new subject follow and?" If not, delete the comma. This is the single most common over-punctuation trap in editing items.

Active vs. Passive Voice

Some editing items reward the active voice, in which the subject performs the action, over the wordier passive voice, in which the subject receives it.

Active sentences are usually clearer and more concise, and they avoid the dangling modifier that passive openings invite: Having finished the report, the deadline was met is wrong because the deadline did not finish anything. Recast it in the active voice — Having finished the report, the team met the deadline — so the noun right after the comma is the one that acted.