Sentence Structure and Punctuation
Domain 2 examines how sentences are built and marked: distinguishing complete sentences from fragments and run-ons, choosing punctuation that matches the grammatical relationship, and keeping parallel structures. The exam rewards you for recognizing where a sentence boundary actually falls.
Sentence boundaries
- A fragment lacks a subject, a finite verb, or an independent clause: Because the deadline moved. Repair it by attaching it to a main clause or supplying the missing part.
- A comma splice joins two independent clauses with only a comma. Fix it with a period, a semicolon, or a comma plus a coordinating conjunction (and, but, or, nor, for, so, yet).
- A fused sentence joins clauses with no punctuation at all.
Punctuation that carries meaning
- Semicolons separate closely related independent clauses and precede conjunctive adverbs (however, therefore, moreover) when a comma follows: The trial ended; however, the data were incomplete.
- Colons follow an independent clause and introduce a list, explanation, or quotation.
- Commas set off nonrestrictive information (My brother, who lives in Ohio, teaches) but not restrictive information that identifies the noun (The brother who lives in Ohio teaches).
- Apostrophes mark possession and contractions, never plural nouns: the teachers' lounge, its versus it's.
Worked example
Original: The study was inconclusive, however, it prompted further research. Reasoning: two independent clauses are joined by only a comma, producing a splice. However is a conjunctive adverb, not a conjunction, so it cannot do the joining. Revision: The study was inconclusive; however, it prompted further research.
Traps
- Using a semicolon before a fragment or before a phrase such as for example that introduces a list.
- Hyphens versus dashes, and dashes used where a colon is required.
- Missing comma after an introductory dependent clause.
- Treating a present participle phrase as a complete sentence.