How do you punctuate sentences correctly and recognize complete sentences, comma splices, run-ons, and fragments, both in editing items and in your own writing?
Punctuation and sentence structure: applying the conventions of capitalization, punctuation (commas, semicolons, colons, apostrophes, and end marks), and correct sentence boundaries, recognizing and fixing comma splices, run-on sentences, and fragments, as tested in editing items and rewarded in the Knowledge of Language and Conventions dimension of the LEAP writing rubrics.
The punctuation and sentence-structure conventions LEAP English I and II expect: commas, semicolons, colons, apostrophes, and correct sentence boundaries, including fixing comma splices, run-ons, and fragments. Tested in editing items and scored in the conventions dimension of the writing rubrics.
Reviewed by: AI editorial process; not yet individually human-reviewed
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What this skill is asking
Punctuation and sentence structure cover how sentences are bounded and joined, and they are tested on LEAP English I and II in revising and editing items and scored in the conventions dimension of the writing rubrics. Louisiana standard L.9-10.2 asks you to demonstrate command of capitalization, punctuation, and spelling, and a large share of editing items target sentence boundaries: comma splices, run-on sentences, and fragments. You will see items that ask which version is punctuated correctly and items that ask you to identify or fix a boundary error. This page covers the main punctuation marks, how to join and separate independent clauses, and how to recognize and repair comma splices, run-ons, and fragments. The transferable skill is controlling where sentences begin and end, which keeps your writing clear and protects the conventions points.
Punctuation and clause boundaries
The heart of this skill is knowing how to join two complete sentences.
The three correct ways to join two independent clauses are: a comma plus a coordinating conjunction ("The storm passed, and we went outside"), a semicolon ("The storm passed; we went outside"), or a period making two sentences. A comma by itself (a splice) and no punctuation at all (a run-on) are both errors. A fragment is usually a dependent clause stranded alone, fixed by attaching it to an independent clause. These rules connect directly to sentence boundaries and combining in the revising-and-editing module and to grammar conventions, and they feed the conventions score on the writing rubric.
Why boundaries count twice
Sentence-boundary control is one of the highest-frequency conventions.
Punctuation beyond clause boundaries, apostrophes for possession and contraction, commas in a series, colons before a list, also appears in editing items and matters for clean writing. But the boundary errors are the highest-leverage targets. Mastering them serves the editing items, the conventions dimension of the rubric, and the clarity of your own sentences all at once. Louisiana standard L.9-10.2 defines the command of mechanics the rubric rewards.
Working a punctuation item
Try this
Q1. What are the correct ways to join two independent clauses? [Recall]
- Cue. Use a comma plus a coordinating conjunction (and, but, so), a semicolon, or a period that makes two sentences. A comma alone (comma splice) and no punctuation (run-on) are both errors.
Q2. Why is "Although the test was hard." a fragment, and how would you fix it? [Short explanation]
- Cue. "Although the test was hard" is a dependent clause; "although" makes it unable to stand alone, so it does not express a complete thought. Fix it by joining it to an independent clause: "Although the test was hard, she finished every question." This is the kind of fragment L.9-10.2 expects you to repair.
Exam-style practice questions
Practice questions written in the style of LDOE exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.
LEAP 2025 English I (style)1 marksWhich sentence is punctuated correctly? (1) 'The storm passed, we went outside.' (2) 'The storm passed; we went outside.' (3) 'The storm passed we went outside.' (4) 'The storm passed, and we, went outside.'Show worked answer →
Answer: (2). Two complete sentences (independent clauses) can be joined with a semicolon, so "The storm passed; we went outside" is correct. They could also be joined with a comma plus a conjunction ("passed, and we went") or split into two sentences.
Why not the others: (1) is a comma splice (a comma alone cannot join two independent clauses); (3) is a run-on (no punctuation between the clauses); (4) misuses a comma after "we," breaking the subject from its verb. Sentence-boundary errors like these are a core editing target under L.9-10.2.
LEAP 2025 English II (style)1 marksWhich is a sentence fragment? (1) 'She finished the race.' (2) 'Because she had trained all summer.' (3) 'The team celebrated.' (4) 'They went home happy.'Show worked answer →
Answer: (2). "Because she had trained all summer" is a dependent clause standing alone; it begins with "because" and does not express a complete thought, so it is a fragment. It needs an independent clause to complete it ("Because she had trained all summer, she won easily").
Why not the others: (1), (3), and (4) each have a subject and a verb and express a complete thought, so they are complete sentences. Recognizing that a subordinating word like "because," "although," or "when" makes a clause dependent is the key to spotting this kind of fragment.
Related dot points
- Grammar and usage conventions: applying the conventions of standard English grammar and usage, including subject-verb agreement, pronoun-antecedent agreement and clear pronoun reference, consistent verb tense, and correct modifier placement, as tested in revising and editing items and rewarded in the Knowledge of Language and Conventions dimension of the LEAP writing rubrics.
The grammar and usage conventions LEAP English I and II expect: subject-verb agreement, pronoun agreement and clear reference, consistent verb tense, and modifier placement. These are tested in editing items and scored in the Knowledge of Language and Conventions dimension of the writing rubrics.
- Vocabulary in context: determining the meaning of unknown and multiple-meaning words and phrases by using context clues (definition, example, contrast, and inference from surrounding sentences), and choosing the meaning that fits the passage, on a LEAP English I or II reading passage where vocabulary is tested in context.
How to determine word meaning in context on a LEAP English I or II passage: using definition, example, contrast, and inference clues, and choosing the meaning that fits the passage rather than a memorized definition. LEAP tests vocabulary in context, often with multiple-meaning words, not as isolated lists.
- Sentence boundaries and combining: recognizing and correcting comma splices, run-on sentences, and fragments, and combining short or choppy sentences into clearer, more varied ones using coordination, subordination, and appositives, on a LEAP English I or II revising and editing item.
How to handle sentence boundaries on a LEAP English I or II item: fixing comma splices, run-ons, and fragments, and combining choppy sentences using coordination, subordination, and appositives for clearer, more varied writing. These boundary skills are tested in editing items and rewarded on the writing rubrics.
- Editing for grammar and usage: identifying and correcting errors in subject-verb agreement, pronoun-antecedent agreement and reference, verb tense, and modifier placement within a draft passage, choosing the correction that follows standard English, on a LEAP English I or II revising and editing item.
How to edit for grammar and usage on a LEAP English I or II item: spotting and fixing subject-verb agreement, pronoun agreement and reference, tense, and modifier errors in a draft, and choosing the correction that follows standard English. The same conventions are scored on the writing rubrics.
- The LEAP writing rubric and scoring: how the two prose constructed-response rubrics work, the analytic rubric for the Literary Analysis and Research Simulation tasks (Reading Comprehension and Written Expression, holistic 0 to 4 times 4, plus Knowledge of Language and Conventions 0 to 3, up to 19) and the narrative rubric for the Narrative Writing Task (Written Expression 0 to 4 times 3, plus conventions 0 to 3, up to 15), the rule that an unscorable response earns 0, and how to write toward the top of each, for LEAP English I and II.
How the LEAP English I and II prose responses are scored: the analytic rubric (Reading Comprehension and Written Expression 0 to 4 times 4, plus conventions 0 to 3, up to 19) for the Literary Analysis and Research Simulation tasks, and the narrative rubric (Written Expression 0 to 4 times 3, plus conventions, up to 15). What each dimension rewards and how to write toward the top.
Sources & how we know this
- LEAP 2025 Assessment Guide for English I and English II — LDOE (2025)
- Louisiana Student Standards for English Language Arts — LDOE (2025)