Complex Sentences and Clause Types
Complex sentences contain one main clause and one or more subordinate clauses. Understanding clause types helps writers vary their sentence structure and create more sophisticated writing.
What You Need to Know
Key Concept Diagram
A main (independent) clause can stand alone as a sentence: "The dog barked."
A subordinate (dependent) clause cannot stand alone; it depends on the main clause: "because it was frightened"
A complex sentence joins a main and subordinate clause: "The dog barked because it was frightened."
Subordinating conjunctions (because, although, when, while, since, unless) introduce subordinate clauses
Key Vocabulary
Main clause
A group of words with a subject and verb that can stand alone as a sentence
Subordinate clause
A clause that depends on the main clause and cannot stand alone as a complete sentence
Subordinating conjunction
A word that introduces a subordinate clause, e.g. because, although, when, unless
Complex sentence
A sentence with at least one main clause and one subordinate clause
Knowledge Check
Select the correct answer for each question. Click "Check Answer" to see if you are right.
Question 1
Identify the subordinate clause: "Although it was raining, we went for a walk."
Question 2
Which word is a subordinating conjunction?
Question 3
Which is a complex sentence?
Key Concepts Summary
- ●A main (independent) clause can stand alone as a sentence: "The dog barked."
- ●A subordinate (dependent) clause cannot stand alone; it depends on the main clause: "because it was frightened"
- ●A complex sentence joins a main and subordinate clause: "The dog barked because it was frightened."
- ●Subordinating conjunctions (because, although, when, while, since, unless) introduce subordinate clauses