AP® English Language and Composition · Big Idea 4 Style: Syntax and Sentence Structure (Skills 7.B, 8.B)
7.B Independent and Dependent Clauses (STL-1.G)
An independent clause stands alone as a complete sentence; a dependent clause has a subordinating word attached that makes it lean on another clause for completion.
A clause is just a subject plus a verb. That's it. 'The bridge closed' has a subject (bridge) and a verb (closed), and it makes a complete claim, so it stands on its own: independent. Put the word 'because' in front of it and nothing about the subject or verb changes, but the clause now can't stand up anymore. 'Because the bridge closed' is true, but it isn't a finished thought. It's waiting for you to say what happened as a result. That's what a subordinating word does: it takes a perfectly good standing clause and tips it over so it has to lean on something else.
The sort always runs through that one word, never through length. A two-word clause like 'rain fell' stands fine. A thirty-word clause can still lean if it opens with 'while' or 'although' or 'since' or 'because'. So when you're sorting clauses, check the first word of each one, not how much information it's carrying. A clause loaded with detail is still leaning if a subordinator is holding it up; a short bare clause is still independent if nothing is attached to its front.
This matters once you start building sentences out of these blocks. A sentence needs at least one independent clause to actually land somewhere; dependent clauses can pile up in front of or behind it, but they can't replace it. Stack three leaning clauses together with no independent clause and you get a sentence that sets up expectation after expectation and never pays it off. That failure is exactly what periodic sentences exploit on purpose, and exactly what careless writers fall into by accident.
Key terms
- independent clause
- A subject-verb unit that makes a complete statement and can stand alone as a sentence.
- dependent clause
- A subject-verb unit preceded by a subordinating word, so it cannot stand alone.
- subordinating word
- A word like because, although, while, or since that attaches to a clause and forces it to lean on another clause.
- subject-verb unit
- The core of any clause: someone or something paired with an action or state.
Watch it explained
- How it worksHow does one subordinating word turn a block that stands up into a piece that has to lean?
- Worked exampleWalk me through sorting although the vote passed and the vote passed into standing and leaning blocks.
- Common mistakeWhy isn't a long clause automatically independent and a short one automatically dependent?
- Going furtherWhat happens to a sentence built out of three dependent clauses and no independent one at all?
Check yourself
End of topic.