4.2 Sentence Structure
Key Takeaways
- Complete sentences have a subject, predicate, and express a complete thought
- Fragments are incomplete; run-ons are improperly joined sentences
- Use coordinating conjunctions (FANBOYS) or semicolons to join independent clauses
- Items in a series must have parallel structure
- Place modifiers close to the words they describe
Understanding sentence structure helps you identify errors and write clear, effective sentences. The ParaPro tests your ability to recognize complete sentences and common structural problems.
Parts of a Sentence
Subject: Who or what the sentence is about Predicate: What the subject does or is (includes the verb)
Example: The excited students | cheered loudly.
- Subject: The excited students
- Predicate: cheered loudly
Sentence Types by Structure
| Type | Definition | Example |
|---|---|---|
| Simple | One independent clause | The teacher explained the lesson. |
| Compound | Two independent clauses joined | The teacher explained, and the students listened. |
| Complex | Independent + dependent clause | When the bell rang, students left. |
| Compound-Complex | Two independent + one dependent | When the bell rang, students left, and they went home. |
Independent vs. Dependent Clauses
| Clause Type | Definition | Example |
|---|---|---|
| Independent | Complete thought; can stand alone | Students left the classroom. |
| Dependent | Incomplete thought; needs more | When the bell rang... |
Subordinating Conjunctions (start dependent clauses):
- Time: when, while, after, before, until
- Cause: because, since
- Condition: if, unless
- Contrast: although, even though
Sentence Errors
Sentence Fragments
Fragment: An incomplete sentence (missing subject, verb, or complete thought)
-
✗ Running down the hall.
-
✓ The student was running down the hall.
-
✗ Because it was raining.
-
✓ We stayed inside because it was raining.
Run-On Sentences
Run-on: Two sentences incorrectly joined
- ✗ I went to school I saw my friends.
Fixes:
- Period: I went to school. I saw my friends.
- Comma + conjunction: I went to school, and I saw my friends.
- Semicolon: I went to school; I saw my friends.
Comma Splices
Comma splice: Two sentences joined only by a comma
- ✗ I went to school, I saw my friends.
Fixes: Same as run-ons
Parallel Structure
Items in a list or series should have the same grammatical form.
Not Parallel:
- ✗ She likes reading, to swim, and basketball.
Parallel:
- ✓ She likes reading, swimming, and playing basketball.
- ✓ She likes to read, to swim, and to play basketball.
Modifier Placement
Misplaced modifiers are in the wrong position:
- ✗ I saw a dog walking to school. (Was the dog walking to school?)
- ✓ Walking to school, I saw a dog.
Dangling modifiers have no clear word to modify:
- ✗ After eating lunch, the bell rang. (The bell ate lunch?)
- ✓ After eating lunch, the students heard the bell ring.
Classroom Application
Help students with sentence structure by:
- Using sentence frames for practice
- Identifying subject and predicate in color
- Teaching fragment vs. sentence identification
- Practicing combining simple sentences
- Reading sentences aloud to check for completeness
Which sentence is a fragment?
Which sentence shows parallel structure?