Comma splice
SAT glossary · Reading & Writing
Definition
Two independent clauses joined by a comma alone — the most tested error in the Boundaries domain. Its disguised form is a conjunctive adverb with commas ('The measure passed, however the vote was close'), where 'however' feels like it is doing the joining but is only an adverb.
Comma splice in plain English
A comma splice happens when you jam two complete, independent sentences together using only a comma, with nothing else connecting them — like 'The measure passed, the vote was close.' This is considered one of the most heavily-tested errors in this whole category of grammar questions. Its sneakiest disguised version uses a word like 'however' right after the comma: 'The measure passed, however the vote was close.' This FEELS like 'however' is doing the job of connecting the two sentences, but 'however' is actually just a descriptive adverb, not a true connector — it cannot legally join two independent sentences with only a comma, no matter how natural it sounds.
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Practice Comma splice
Which choice correctly joins the two ideas without a comma splice or run-on sentence?
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