Fragments & Run-Ons
Learn to spot sentence fragments, run-ons, and comma splices in Grade 7 ELA — plus five reliable ways to repair a boundary between two independent clauses.
What you'll do in this lesson
A voice-first session with the Crimsora tutor on Fragments & Run-Ons, then targeted practice and FRQs — with the tutor adapting to where you get stuck.
What this lesson covers
Every sentence you write makes a promise: it will tell the reader who or what, and what happened. A fragment breaks that promise by stopping too soon. A run-on breaks it by jamming two finished thoughts together with no clear signal that one has ended. Both are boundary problems — the writer either put a period where a sentence was not finished, or failed to put anything where one was.
In this lesson you will learn a two-question test that identifies a complete sentence, the four fragment types that show up most often in student writing, and the difference between a fused run-on and a comma splice. Then you will learn five repair moves for run-ons, so you can pick the one that fits your meaning instead of just dropping in a period every time. By the end, you should be able to read your own draft aloud and hear where a sentence really ends.
In this lesson you will learn a two-question test that identifies a complete sentence, the four fragment types that show up most often in student writing, and the difference between a fused run-on and a comma splice. Then you will learn five repair moves for run-ons, so you can pick the one that fits your meaning instead of just dropping in a period every time. By the end, you should be able to read your own draft aloud and hear where a sentence really ends.
The Two-Question Test for a Complete Sentence
A complete sentence is built on an independent clause: a group of words with a subject, a verb that goes with that subject, and no word at the front that leaves the thought hanging.
Ask two questions of any group of words punctuated as a sentence. First, who or what is this about? That is the subject. Second, what does the subject do or what is it? That is the verb. If you cannot answer both, you have a fragment.
There is a third trap. Sometimes both answers exist, but a subordinating conjunction at the front (because, although, when, since, if, while, after, unless) turns the whole thing into a dependent clause. Compare: "The bus was late" answers both questions and stands alone. "Because the bus was late" answers both questions too — subject bus, verb was — but the word because makes the reader wait for the rest. It cannot stand alone.
Watch out for verb forms that only look like verbs. Words ending in -ing are not verbs by themselves. "The players running toward the net" has no working verb; "The players were running toward the net" does. The little helping verb is what turns running into an actual predicate.
Length proves nothing. "Stop." is a complete sentence — the subject you is understood in a command. Meanwhile "A long silver train pulling slowly into the crowded downtown station on a rainy Tuesday morning" is fifteen words and still a fragment, because nothing is ever said about the train.
Ask two questions of any group of words punctuated as a sentence. First, who or what is this about? That is the subject. Second, what does the subject do or what is it? That is the verb. If you cannot answer both, you have a fragment.
There is a third trap. Sometimes both answers exist, but a subordinating conjunction at the front (because, although, when, since, if, while, after, unless) turns the whole thing into a dependent clause. Compare: "The bus was late" answers both questions and stands alone. "Because the bus was late" answers both questions too — subject bus, verb was — but the word because makes the reader wait for the rest. It cannot stand alone.
Watch out for verb forms that only look like verbs. Words ending in -ing are not verbs by themselves. "The players running toward the net" has no working verb; "The players were running toward the net" does. The little helping verb is what turns running into an actual predicate.
Length proves nothing. "Stop." is a complete sentence — the subject you is understood in a command. Meanwhile "A long silver train pulling slowly into the crowded downtown station on a rainy Tuesday morning" is fifteen words and still a fragment, because nothing is ever said about the train.
Four Kinds of Fragments and How to Repair Them
Fragments come in predictable shapes. Learning the shapes is faster than reading each sentence a dozen times.
The most common repair is the simplest: a fragment usually belongs to the sentence right next to it. Look left and look right before you start adding words. "I stayed home. Because I had a fever." becomes "I stayed home because I had a fever." Notice that no comma is needed when the because clause comes second.
Where students go wrong is treating every fragment as a missing-word problem and stuffing in a subject that already exists somewhere nearby. That produces clunky repetition: "I stayed home. I had a fever because I had a fever." Read the two pieces together first.
One more note: skilled writers sometimes use fragments on purpose — in dialogue, in advertising, for emphasis. "Not a chance." That is a stylistic choice, and in academic writing for class you should assume your teacher wants complete sentences unless you are writing fiction.
| Fragment type | Example | What is missing | Repair |
|---|---|---|---|
| Subordinate clause | Although she practiced every day. | Nothing to complete the thought | Attach it: Although she practiced every day, she still felt nervous. |
| Missing verb | The dog on the porch with muddy paws. | A predicate | Add one: The dog on the porch had muddy paws. |
| Missing subject | Ran all the way to the corner store. | Who ran | Add one: Marcus ran all the way to the corner store. |
| Added-on phrase | We ordered pizza. And also wings and a salad. | A subject and verb | Join it: We ordered pizza, wings, and a salad. |
Where students go wrong is treating every fragment as a missing-word problem and stuffing in a subject that already exists somewhere nearby. That produces clunky repetition: "I stayed home. I had a fever because I had a fever." Read the two pieces together first.
One more note: skilled writers sometimes use fragments on purpose — in dialogue, in advertising, for emphasis. "Not a chance." That is a stylistic choice, and in academic writing for class you should assume your teacher wants complete sentences unless you are writing fiction.
Run-Ons, Fused Sentences, and Comma Splices
A run-on happens when two independent clauses are pushed together without the punctuation or connecting word that marks the boundary. There are two flavors.
A fused sentence has nothing at all between the clauses: "The rain stopped we went outside." A comma splice has a comma doing a job it cannot do alone: "The rain stopped, we went outside." A comma is a pause, not a stop. By itself it is too weak to hold two complete sentences apart.
To find them, use the same two-question test twice. Cover the second half and ask whether the first half is a complete sentence. Then cover the first half and ask about the second. If both halves pass, the words between them must be strong enough to separate them.
Five repairs work, and each one changes the sound and the meaning slightly.
The fourth repair is the one students underuse, and it usually produces the best sentence, because it tells the reader how the two events relate instead of just parking them side by side.
A fused sentence has nothing at all between the clauses: "The rain stopped we went outside." A comma splice has a comma doing a job it cannot do alone: "The rain stopped, we went outside." A comma is a pause, not a stop. By itself it is too weak to hold two complete sentences apart.
To find them, use the same two-question test twice. Cover the second half and ask whether the first half is a complete sentence. Then cover the first half and ask about the second. If both halves pass, the words between them must be strong enough to separate them.
Five repairs work, and each one changes the sound and the meaning slightly.
| Repair | Result | Best when |
|---|---|---|
| Period | The rain stopped. We went outside. | The ideas are separate |
| Semicolon | The rain stopped; we went outside. | Ideas are tightly linked |
| Comma plus and, but, or, so, for, nor, yet | The rain stopped, so we went outside. | You want to name the relationship |
| Subordinating conjunction | When the rain stopped, we went outside. | One idea depends on the other |
| Semicolon plus however, therefore, then | The rain stopped; therefore, we went outside. | You want a formal transition |
The Traps That Fool Careful Writers
Some words feel like connectors but cannot join two independent clauses with only a comma. The big offenders are however, therefore, then, also, instead, moreover, in fact, and for example. These are transition words, not coordinating conjunctions. "The test was hard, however I finished it" is a comma splice. Fix it with a semicolon before and a comma after: "The test was hard; however, I finished it." Or split it: "The test was hard. However, I finished it."
Only seven words work with a comma to join clauses — for, and, nor, but, or, yet, so. Remembering the group as FANBOYS helps, but remember the comma goes before the conjunction, not after it.
A second trap is assuming that length signals the error. Students often "fix" a long, correct sentence by chopping it into fragments, and leave a short splice like "It rained, we left" untouched. The number of words is irrelevant; the number of independent clauses is everything.
A third trap is the compound predicate. "Jamal opened the door and waved to his cousin" has one subject and two verbs — that is a single clause, and no comma belongs before and. Compare "Jamal opened the door, and his cousin waved" — now there are two subjects and two full clauses, so the comma is correct. Ask whether the words after and could stand alone as a sentence.
Finally, trust your ear only after you trust your test. Reading aloud helps you hear where you naturally stop, but the two-question test is what confirms it.
Only seven words work with a comma to join clauses — for, and, nor, but, or, yet, so. Remembering the group as FANBOYS helps, but remember the comma goes before the conjunction, not after it.
A second trap is assuming that length signals the error. Students often "fix" a long, correct sentence by chopping it into fragments, and leave a short splice like "It rained, we left" untouched. The number of words is irrelevant; the number of independent clauses is everything.
A third trap is the compound predicate. "Jamal opened the door and waved to his cousin" has one subject and two verbs — that is a single clause, and no comma belongs before and. Compare "Jamal opened the door, and his cousin waved" — now there are two subjects and two full clauses, so the comma is correct. Ask whether the words after and could stand alone as a sentence.
Finally, trust your ear only after you trust your test. Reading aloud helps you hear where you naturally stop, but the two-question test is what confirms it.
Key terms
- Independent clause.
- A group of words with a subject and a matching verb that expresses a complete thought and can stand alone as a sentence.
- Dependent (subordinate) clause.
- A clause that has a subject and verb but begins with a word like because, although, or when, so it cannot stand alone.
- Sentence fragment.
- A group of words punctuated as a sentence that is missing a subject, a verb, or a completed thought.
- Run-on sentence.
- Two or more independent clauses joined without adequate punctuation or a connecting word.
- Fused sentence.
- A run-on with no punctuation at all between the two independent clauses.
- Comma splice.
- Two independent clauses joined by only a comma, which is too weak to separate complete sentences.
- Coordinating conjunction.
- One of the seven joining words — for, and, nor, but, or, yet, so — that can link two independent clauses when preceded by a comma.
- Conjunctive adverb.
- A transition word such as however, therefore, or moreover that shows a relationship but cannot join clauses with only a comma.
Worked example
Find and correct every fragment, fused sentence, and comma splice in this paragraph. Explain each fix.
Our science fair project almost fell apart the night before it was due. Because the poster board got soaked in the rain. My partner panicked, I told her we still had time. We printed new charts we taped them onto a piece of cardboard from the recycling bin. Which actually looked better than the original.
Our science fair project almost fell apart the night before it was due. Because the poster board got soaked in the rain. My partner panicked, I told her we still had time. We printed new charts we taped them onto a piece of cardboard from the recycling bin. Which actually looked better than the original.
Work sentence by sentence, applying the two-question test to each group of words.
Sentence 1 is fine: subject project, verb fell apart, complete thought.
"Because the poster board got soaked in the rain." This has a subject and a verb, but because leaves the thought hanging — a subordinate clause fragment. It explains the sentence before it, so attach it: Our science fair project almost fell apart the night before it was due, because the poster board got soaked in the rain. (You may also drop the comma; both are acceptable here.)
"My partner panicked, I told her we still had time." Cover each half: My partner panicked stands alone, and I told her we still had time stands alone. Two independent clauses joined by a comma is a comma splice. The best repair names the relationship: My partner panicked, but I told her we still had time. A semicolon would also work.
"We printed new charts we taped them onto a piece of cardboard." Both halves are complete and nothing separates them — a fused sentence. These are steps in a sequence, so join them with a comma plus and: We printed new charts, and we taped them onto a piece of cardboard from the recycling bin.
"Which actually looked better than the original." No subject that can stand alone; which points back to the cardboard. Attach it to the sentence before with a comma: ...from the recycling bin, which actually looked better than the original.
Final paragraph: Our science fair project almost fell apart the night before it was due, because the poster board got soaked in the rain. My partner panicked, but I told her we still had time. We printed new charts, and we taped them onto a piece of cardboard from the recycling bin, which actually looked better than the original.
Sentence 1 is fine: subject project, verb fell apart, complete thought.
"Because the poster board got soaked in the rain." This has a subject and a verb, but because leaves the thought hanging — a subordinate clause fragment. It explains the sentence before it, so attach it: Our science fair project almost fell apart the night before it was due, because the poster board got soaked in the rain. (You may also drop the comma; both are acceptable here.)
"My partner panicked, I told her we still had time." Cover each half: My partner panicked stands alone, and I told her we still had time stands alone. Two independent clauses joined by a comma is a comma splice. The best repair names the relationship: My partner panicked, but I told her we still had time. A semicolon would also work.
"We printed new charts we taped them onto a piece of cardboard." Both halves are complete and nothing separates them — a fused sentence. These are steps in a sequence, so join them with a comma plus and: We printed new charts, and we taped them onto a piece of cardboard from the recycling bin.
"Which actually looked better than the original." No subject that can stand alone; which points back to the cardboard. Attach it to the sentence before with a comma: ...from the recycling bin, which actually looked better than the original.
Final paragraph: Our science fair project almost fell apart the night before it was due, because the poster board got soaked in the rain. My partner panicked, but I told her we still had time. We printed new charts, and we taped them onto a piece of cardboard from the recycling bin, which actually looked better than the original.
Practice questions
Which sentence contains a comma splice?
- The gym was crowded, so we practiced outside on the blacktop.
- The gym was crowded, we practiced outside on the blacktop.
- Because the gym was crowded, we practiced outside on the blacktop.
- The gym was crowded and noisy, especially near the doors.
Answer: The gym was crowded, we practiced outside on the blacktop.
Test each half of the correct answer: "The gym was crowded" is a complete sentence, and "we practiced outside on the blacktop" is also a complete sentence. Only a comma separates them, and a comma alone cannot hold two independent clauses apart. The first option adds the coordinating conjunction so, which makes the comma legal. The third option turns the first clause into a dependent clause with because, so there is only one independent clause. The fourth option has one subject and one verb; especially near the doors is a phrase, not a clause.
Rewrite this run-on two different ways, using a different repair each time, and explain how the meaning changes: "The power went out our whole street was dark for three hours."
Answer: Sample answers: (1) "The power went out, so our whole street was dark for three hours." (2) "When the power went out, our whole street was dark for three hours." A semicolon version — "The power went out; our whole street was dark for three hours." — also works.
Both halves pass the two-question test, so this is a fused sentence. The comma-plus-so version states a cause-and-effect relationship directly: the outage caused the darkness. The when version subordinates the first clause, which shifts the emphasis onto the three hours of darkness and treats the outage as background timing. The semicolon version links the ideas tightly but leaves the reader to infer the relationship. Choosing among repairs is a meaning decision, not just a punctuation decision.
Explain why "A tall stack of library books balanced on the edge of her desk" is a fragment, and correct it.
Answer: It has no working verb, so nothing is ever said about the stack of books. Corrected: "A tall stack of library books balanced on the edge of her desk and finally toppled over." Or: "A tall stack of library books was balanced on the edge of her desk."
The word balanced looks like a verb, but here it is a participle describing the stack — the same trap as an -ing word with no helping verb. Ask what the stack of books actually does, and there is no answer. Adding the helping verb was creates a predicate, or you can supply a real action verb such as toppled. Notice that the fragment is thirteen words long: length never tells you whether a group of words is complete.
FAQ
- Can a sentence start with because?
- Yes, as long as the sentence finishes the thought. "Because the road was closed, we took the long way home" is correct — the dependent clause comes first, a comma follows it, and then an independent clause completes the sentence. What is not correct is stopping after the because part: "Because the road was closed." That is a fragment. The rule your teacher may have simplified into "never start with because" is really "never end after because."
- What is the difference between a run-on and a comma splice?
- They are the same underlying error with different punctuation. Both put two independent clauses together without an adequate boundary. A fused run-on has nothing between the clauses at all; a comma splice has a comma, which is too weak to do the job. The same five repairs fix both: a period, a semicolon, a comma plus one of the FANBOYS, a subordinating conjunction, or a semicolon plus a transition word.
- Is a very long sentence automatically a run-on?
- No. A sentence can be forty words long and perfectly correct if its clauses are properly joined, and a four-word sentence like "It rained, we left" can be a run-on. What matters is how many independent clauses are present and what separates them, not how many words there are.
- Are fragments ever okay in writing?
- In fiction, dialogue, poetry, and advertising, writers use fragments deliberately for rhythm and emphasis. "Not this time." In the essays, lab write-ups, and analysis paragraphs you produce for class, assume complete sentences are expected. The difference between a stylistic fragment and a mistake is whether you can explain why you chose it.
Learn this with a teacher, not a page
The Crimsora tutor teaches Fragments & Run-Ons live — explaining on a whiteboard, asking you questions, and adapting to where you get stuck.