Revising Sentence Fragments, Run-On Sentences, and Comma Splices
You cannot write a paragraph clearly if you cannot write clear sentences. Clear sentences are well-ordered, well-constructed sentences. The two most common sentence structure errors in student papers are run-on sentences and sentence fragments.
- Independent Clauses and Simple Sentences
- Subordinate Clauses and Complex Sentences
- Compound Sentences
- Common Sentence Errors
A variety of sentence types will always be more interesting to your reader than using the same type and length repeatedly.
A subject is usually a noun (person, place, thing, idea) or a pronoun (a word that substitutes for and refers to a noun: e.g. "he" for "Sam"). The subject of a sentence is the noun or pronoun that name who or what the sentence is about:
In a compound sentence, simple sentences become known as independent clauses; the two independent clauses together make up a compound sentence. The coordinating conjunction must be preceded by a comma when you want to join two independent clauses into a compound sentence. For example:
Coordinating conjunctions can be used for many different reasons, so you don't always need to put a comma before ‘and’. This rule applies only when you join two independent clauses to make a compound sentence. For example:
The first example is a compound sentence with two independent clauses joined by ‘and’. The second is a simple sentence consisting of one independent clause with one subject and two verbs (or one verb used twice). For the simple sentence, a comma before ‘and’ is unnecessary.
The comma which comes after ‘nevertheless’ in the example is optional, but the semi-colon is required. Words like these have several different names: sentence connectors, transitional words/phrases, conjunctive adverbs, adverbial connectives.
Words: accordingly, also, besides, consequently, finally, first, furthermore, hence, however, indeed, instead, likewise, moreover, nevertheless, next, nonetheless, otherwise, second, similarly, still, then, therefore, thus
Phrases: all in all, as a result, as an illustration, for example, for instance, for this purpose, in addition, in any event, in contrast, in fact, in general, on the contrary, on the other hand, on the whole, that is, to illustrate
A compound-complex sentence consists of two or more independent clauses and one or more subordinate clauses. For example:
I like the look of Dalmatians; however, I suspect that they are too high-strung to be good pets.
It is helpful to identify the sentence elements in the preceding example:
- independent clause: I like the look of Dalmatians
- semi-colon and adverbial connective: ; however,
- subordinate clause with relative pronoun: I suspect that
- independent clause: they are too high-strung to be good pets.
This example follows a different pattern:
Since we rely on mobile technologies, network outages cause serious problems, and we lack necessary safeguards for citizens, businesses, and governments.
- subordinate clause: Since we rely on mobile technologies,
- independent clause: network outages cause serious problems
- comma and coordinating conjunction: , and
- independent clause: we lack necessary safeguards for citizens, businesses, and governments.
A subordinate clause has a subject and a verb, but it cannot stand alone as a sentence. Subordinate clauses begin with certain words or short phrases called subordinating words (also known as dependent words, or subordinating/subordinate conjunctions). If a clause begins with a subordinating word, that clause is a subordinate clause and cannot stand alone as a sentence.
Subordinating words: after, although, as, as if, as long as, because, before, even if, even though, ever since, if, in order that, provided that, since, so that, than, that, though, unless, until, what, whatever, when, whenever, where, whereas, wherever, whether
A subordinate clause must be attached to an independent clause. If it is not, it becomes a sentence structure error called a sentence fragment. The above examples of subordinate clauses are fragments; they can be corrected by combining each with an appropriate independent clause, and making complex sentences:
Subordinate means of lesser importance. In a compound sentence, the clauses are both independent, and both the ideas they convey are given equal emphasis. In contrast, in a complex sentence, the idea in the subordinate clause is not given equal emphasis; that is why the writer chooses to put it in the subordinate clause, thereby emphasizing the idea of the independent clause.
The writer of this sentence wants to emphasize the idea of the independent clause - that "she was honest," and to place less emphasis on the idea of the subordinate clause - that "she was penalized for plagiarism."
Here, the writer is emphasizing that “she was penalized for plagiarism" and placing less emphasis on the fact that "'she was basically honest." The difference between the two sentences is subtle but clear.
Remember that every independent clause must have a subject and a verb and that every sentence must have at least one independent clause. Any group of words written that does not have both a subject and a verb is a sentence fragment.
- Connect subordinate clause to independent clause to make a complex sentence.
- Introduce missing element (subject or verb).
- Connect to preceding or following sentence.
Sentence fragments increasingly are used in writing for social media, the internet, newspapers, and other kinds of non-academic writing. Despite their popularity, they remain grammatically incorrect and inappropriate for academic and other kinds of formal writing.
An independent clause has a subject and a verb and can stand alone as a simple sentence. By identifying independent clauses you can avoid two of the most common errors in student writing, known as run-on sentences and comma splices.
It becomes clear that the above contains two simple sentences or two independent clauses, each with its own subject-verb. It is a run-on sentence because it is written as if it were only one sentence with no punctuation to show the reader where the first clause ends and the second begins.
- Use a coordinating conjunction to join the two clauses and make a compound sentence.