Understanding Dependent Clauses & Sentence Fragments
A dependent clauseis made up of a subject and a predicate but cannot stand alone as a sentence. A dependent clause must be joined to an independent clause. A detached dependent clause is called a sentence fragment. Although sentence fragments can be used intentionally, writers must first understand the differences between dependent and independent clauses.
Dependent clauses function as either adverb clauses or adjective clauses.
Adverb clauses begin with subordinating conjunctions (dependent clause markers) and answer questions about the independent clause: How? Why? When? Under what circumstances?
Until the polar bear emerges from her den, the researchers will not be able to film her activities.
(The adverb clause tells when and under what circumstances the researcherswill be able to film.)
The following is a list ofsubordinating conjunctions. Recognizing these words may help to identify and repair stand-alone dependent clauses (sentence fragments).
Subordinating Conjunctions and the Relationships They Express
time / after, before, once, since, until, when, whenever, whilereason or cause / as, because, since
result or effect / in order that, so, so that, that
condition / if, even if, provided that, unless
contrast / although, even though, though, whereas
location / where, wherever
choice / than, whether
Revision Strategies:
If you find a stand-alone dependent clause, read the sentences immediately preceding and following the dependent clause to see if you can attach it to one of them. This creates a complex sentence.
We all watched the film American Beauty. After Sarah turned out the light. The class really enjoyed it.
Identify the dependent clause, and decidewhich independent clause you could attach it to.
Another way to repair a dependent clause fragment is to eliminate the subordinating conjunction. See what happens to the following dependent clauses when the subordinating conjunction is removed:
AfterSarah turned out the light . . . (dependent)
BecauseSarah turned out the light . . .(dependent)
Even ifSarah turned out the light . . .(dependent)
AlthoughSarah turned out the light . . .(dependent)
Sarah turned out the light. (independent)
Punctuation:
Use a comma after an opening dependent clause. If the dependent clause follows the independent clause in the sentence, the comma is necessary only when the information is essential to the meaning of the sentence:
Avoid approaching mastiffs unless they are familiar with your scent. (No comma needed; dependent clause essential to meaning of the sentence.)
The tornado seemed to last thirty minutes, even though it passed over in three. (Comma used because dependent clause not essential to meaning of the sentence.)
Another type of dependent clause is an adjective clause. Adjective clauses (alsocalled relative clauses) begin with pronouns or adverbs and modify the preceding noun.
Relative Pronouns
/ Relative Adverbswho, which, that / when, where
The dress that Mary bought for the prom is too frilly. [The adjective clause describes the noun “dress.”]
The eveningwhen Mary can wear her prom dress is getting closer. [The adjective clause modifies the noun “evening.”]
Punctuation:
Use commas around a relative clause only if the information in the clause is not needed for the main idea of the sentence to be understood (also called non-restrictive or non-essential clauses). Note that the meaning of the two following sentences is slightly altered by the comma.
Our house, which is fifty years old, needs major repairs.
Our house which is fifty years old needs major repairs.
Compiled by Jane Addison, Director of the WritingCenter—Spring 2008
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