A complex sentence is a sentence that is formed by joining an independent clause with a dependent clause. An independent clause is a simple sentence and contains a subject, a verb, and expresses a complete thought.
A dependent clause is a clause that has a subject and a verb, but, by itself, does not express a complete thought. Dependent clauses are also called subordinate clauses because they are sub sentences or something less than sentences.
In a complex sentence, the dependent clause always begins with a subordinating conjunction. There are many words in the English language that function as subordinating conjunctions; the table below contains only a partial list.
|Subordinating conjunctions used to indicate when|
|after, before, until (till)1, when, while|
|I couldn't go home until I met my friend downtown.|
|Subordinating conjunctions used to indicate a cause or result.|
|as, because, since, whereas|
|Since it was raining, we had to cancel the picnic.|
|Subordinating conjunctions used to indicate a condition or exception.|
|even though, although, if, though, unless|
|If you come with me, I'll treat you to dinner.|
Caution: Many writers create sentence fragments by writing dependent clauses without a corresponding independent clause. In the following examples, notice the subordinating conjunction at the beginning of the clause.
Each of the fragments above can be corrected by adding an independent clause. The independent clause can be added to either the beginning of the sentence fragment or the end. For example,
Note: When the subordinate clause begins the sentence a comma is needed after the dependent clause.
When the independent clause begins the sentence no comma is needed.
Identify the subordinating conjunction and the dependent clause in the following complex sentences.
Click the sentence to see the correct answer.
1Till is a shortened form of until and is used more often in spoken English than in written English.
Till may be used in informal writing but should not be used in formal writing.