MEMOS for Developmental Writers

Major Sentence errors

2 June 2006

MAJOR sentence error #1: sentence fragments

All of us speak in fragments some of the time, and it sometimes seems that some of us speak in fragments all of the time, but that is certainly not true, even for certain presidential candidates. What we have to realize is that our academic writing cannot contain accidental sentence fragments because it cannot contain fragments of ideas, or accidents.

You already know that a complete sentence can almost never contain all of the meaning or information you wish to convey to a reader; that's why we have paragraphs and collections of paragraphs called essays, reports, memos, books, and so on. But each sentence of a paragraph or group of paragraphs must contain enough complete information so that in combination with other sentences it conveys complete meaning to a reader.

What kinds of fragments do we write? Most student fragments are mispunctuated sentences, basically, dependent clauses with periods after them instead of commas:

When the dog barked. The cat jumped.

That kind of error.

Because this sentence fragment is very short and is isolated on the web page from other sentences and word groups. You'll probably have no trouble noticing that there is something wrong with them. But hide a fragment within a paragraph or an essay, and the odds that you or I will overlook one or more of them increase exponentially. In fact, I just tried to slip a fragment past you. Did you spot the fragment? Do you see how to fix the problem?

Here's the fragment:

Because this sentence fragment is very short and is isolated on the web page from other sentences and word groups.

The word that causes the problem is the subordinating conjunction because. We could repair the problem by deleting because, but we shouldn't want to do the repair that way because the word because adds meaning and coherence to our sentence and paragraph.

Here the better fix:

Because this sentence fragment is very short and is isolated on the web page from other sentences and word groups, you'll probably have no trouble noticing that there is something wrong with them.

But some errors are more insidious. These are the missing word fragments.

While the dog was barking, the cat jumping.

Since a reader's natural tendency is to make sense even where sense is missing, some readers may subconsciously insert the missing helping verb and read the sentence as it was meant to be:

While the dog was barking, the cat was jumping.

"Some readers" who may subconsciously insert the missing helping verb include the writers of such sentences. Have you ever read over something you've written and completely missed a mistake that a re-reading an hour or a day later suddenly discovered? I have. Everyone has.

The whole trick to correcting sentence fragments, and indeed all errors, is to see them. Once you spot a mistake, it's usually easy to correct. With fragments, just connect the fragment with a complete thought or add the missing word or correct the mistaken punctuation.

How do you spot fragments? Here's one way:

How does this work? Reading backwards, sentence-by-sentence, short-circuits your brain's natural tendency to create meaning and meaningful connections even when meaning and meaningful connections are missing. Have you ever looked at a Rorschach inkblot? Your brain will desperately try to impose some kind of image upon a splash of ink that contains no image. With sentences, your brain will insert the word that seems to best complete the incomplete meaning of a sentence fragment. And it will do so without any conscious effort on you part.

MAJOR sentence error #2: run-on (Fused) sentences


A fused sentence is actually two sentences (two independent clauses) connected without any punctuation or joining words. Usually, the second sentence (the second independent clause) in a fused sentence doesn't begin with a capital letter.

Fused sentences are really fairly rare. They are, like comma splices, almost always products of hasty writing and hasty proofreading.

Here's an example:

The dog barked the sudden sound frightened the burglar.


The dog barked. The sudden sound frightened the burglar. (more repairs below under comma splices)

Note the absence of punctuation or words or capitalization between the two clauses above.

Fused sentences are as easy to repair as comma splices. The list of comma splice repairs below will also work to repair fused sentences.

MAJOR sentence error #3:comma splices

Run-on's, also known as fused sentences, are almost always errors of haste. You get in a hurry you forget to put a period between a pair of sentences, as I just did.

Comma splices are a bit trickier because they usually result from a misunderstanding of a rule, most often the rule that requires a coordinating conjunction after a comma separating two independent clauses.


A comma splice is a major sentence error in which two independent clauses are separated (or held together, depending upon point of view) by a comma and, this is the important part, no coordinating conjunction.

Comma splices are almost always the products of hasty writing and hasty proofreading.

Here's an example:

The dog barked, the sudden sound frightened the burglar.

Comma splice repair 1:

The dog barked, and the sudden sound frightened the burglar. (by adding an appropriate coordinating conjunction, and)

Comma splice repair 2:

The dog barked; the sudden sound frightened the burglar. (by changing the comma to a semi-colon)

Comma splice repair 3:

The dog barked; undoubtedly, the sudden sound frightened the burglar. (Change the comma to a semi-colon and add a conjunctive adverb to the following clause.)

Comma splice repair 4:

The dog barked. The sudden sound frightened the burglar. (Change the comma to a period.)

Check your understanding of fragments and run-ons by taking this online quiz.

Major Sentence Error #4: subject-verb agreement

In English sentences, subjects and their verbs must agree in number, gender, and person. The vast majority of subject-verb agreement errors are number errors made in the third person, present tense singular.

Here is an example:

The kite with two tails fly badly.

What word is the subject? kite

What word is the verb? fly

The kite fly badly? No. We must add an s to fly because kite is singular and to agree in number with the subject kite the verb fly must also be singular; it must end with an s: flies. Oddly enough, we end a noun with an s to make it plural; however, we end a verb with an s to make it singular.

A subject-verb agreement chart:

Person Singular Plural
First I fly. We fly.
Second You fly. You fly.
Third He/she/it flies. The kite flies. They fly.


One reason subject-verb agreement errors can be hard to spot is that in many if not most sentences you will have written words between the subject and verb, as in the example sentence above, where a prepositional phrase -- with two tails -- separates the subject from the verb. It's all too easy to mistake the object of the preposition -- tails, a noun, -- for the subject of the sentence, and mistakenly think that the subject of the sentence is plural and then make the sentence's verb plural by leaving off the -s ending.

I hope that's clear. Just remember that the object of a preposition can never be the subject of the sentence. When you're looking for a sentence's subject, mentally delete all of the prepositional phrases and you'll find that locating the subject and verb is much easier.

The kite with two tails flies badly.

Just a few more words about subject-verb agreement:

Subject-verb agreement errors are grammar errors, but no one is ever really confused by them. The real danger in publishing a subject-verb agreement error lies in the impression it will make on your reader, who may uncharitably arrive at the conclusion that you are (a) ignorant of the rules of grammar, (b) oblivious to the consequences of making such errors, or (c) indifferent to the impression you're making. None of these impressions may be accurate; you might have just goofed and then overlooked the goof while proofreading. You did know better. Too bad. Whatever went wrong is your responsibility.

Southerners are especially prone to subject-verb agreement errors. As I noted in class, Southerners tend to drop final sounds on many words as they speak, and that tendency carries over to their writing. After all, we largely write as we speak. So for many Southerners, the tendency to drop the final -s in third-person, present tense, singular verbs is a cultural one. Those dropped -g's and -s's are part of the dialect we hear every day and sometimes even speak. To overcome this tendency, if you have it, you must begin to listen to yourself and to others as they speak. When you do begin to truly hear how people speak, you will be amazed at the number of errors that you will begin hearing. You will be amazed at the number of errors you hear yourself making. And you will begin, slowly at first, to catch yourself, and then to correct yourself, at first only after you have spoken, then as you are speaking, and finally, before you have spoken. You will have arrived. You will have become your own feedback mechanism, your own teacher.


The four errors discussed in this memo often mean the difference between a passing and a failing grade on a writing assignment. They are easy errors to make; in fact, all writers make them at one time or another. Some writers even make them deliberately, for special effect. All writers must learn how to recognize them and how to correct them. The good news is that once recognized these errors are easily corrected.

Read Evergreen's Chapter 26 and LBH's Chapters 17 and 18 for more information on sentence fragments, run-ons, and comma splices. Read Evergreen's Chapter 27 and LBH's Chapter 15A for more information on subject-verb agreement.