Has your word processing program ever advised you to reconsider a sentence you just wrote? Have you ever sat and puzzled over it in frustration, wondering what it was so upset about?
Maybe your sentence wasn’t really a sentence, after all. But how can you tell? What sets apart a real, honest-to-goodness sentence from a phrase or a fragment?
Well, you came to the right place for a simple, no-nonsense explanation.
Every sentence must have a subject, as well as a verb which tells what the subject is doing or being. It must express a complete thought, however brief. If you don’t have those ingredients, then you don’t have a sentence.
“Noun” is the technical term for words that name something, most often a person, a place, or a thing. For example, “woman,” “lake,” and “car” are all nouns. “Woman” is the English name for a female human, while “lake” names a medium-sized body of non-flowing water and “car” names a type of vehicle. Other, less tangible things can also be nouns, such as emotions or ideas.
Every sentence must be about something or, to put it another way, it must have a subject. That subject has to be a noun. For example, take the sentence “The ball is green.” This sentence is about a ball. “Ball” is a name (noun) for a round object. While “green” is also a name (noun), it is not what the sentence is about so it cannot function as the subject of this sentence. Of course, it certainly could form the subject of a different sentence, such as “Green is my favorite color.”
So, to have a sentence, there must be a naming word (noun) that lets the reader know what the sentence is about.
Just sticking in a noun doesn’t make a string of words into a sentence, no matter how long the string of words becomes. “Is green” doesn’t become a sentence even though it contains the noun “green,” because it doesn’t tell you what is green. Clearly, this is a fragmentary thought, and that’s why such phrases are labeled “fragments.” Nor does it help to pile on more words. “Is lovely, pale, luminescent lime green” does not magically transform this into a sentence. There is still no clue as to what it’s talking about.
I’ll throw in one other tidbit about nouns, just for free, though it has nothing to do with determining whether or not you have a complete sentence as opposed to a fragment. But I find that people frequently have trouble with this next concept.
There are common nouns and proper nouns. Common nouns are, as might be expected, ordinary naming words, usually somewhat generic. All my sentence examples above use generic, common nouns: woman, lake, car, ball, green. They can refer, at least potentially, to any woman, any lake, any car.
Proper nouns, on the other hand, are the specific names given to only one thing. Not just any woman, but one specific woman: Hilary Clinton, for example. Not just any lake, but the one named Lake Tahoe. Not just any car, but your neighbor’s new Camaro.
Notice that proper nouns always get capitalized, while common nouns do not. Usually this is fairly obvious, but once in awhile it can get tricky. For instance, “mother” is a common noun because it can potentially be naming anybody’s mom. But if you start talking about your own mom and using the word in the sense that it’s the name you call her, then the word magically transforms into the proper noun “Mother,” because now it’s the specific name of one specific person. Note that this only happens if you start using it as if it was her name. If you say, “I went to town with my mother,” you’re describing who she is (my mother) rather than naming her (Mom).
Okay, so there must be a subject in every sentence, a naming word (noun) that lets the reader know what or who the sentence is about. Let’s go on to the other essential ingredient of a sentence: the verb.
Verbs are action words or words that describe a state of being. Verbs tell what the subject is doing or being. Again, there could potentially be several verbs in a sentence, but there has to be at least one that tells about the subject.
In our sample sentence, “The ball is green,” we’ve already established that it’s talking about the ball. That’s the subject. Now, there’s no action going on in the sentence, but there’s still a verb. It’s a “state-of-being” verb, the little word “is.” What happens if we leave it out? “The ball green.” Sounds like someone who can’t speak English well, like what we imagine a caveman might say, with a few grunts thrown in for good measure.
“The pitcher threw the ball” has an action verb, “threw.” It tells what the subject (pitcher) did.
Sentences can be extremely simple, consisting of little more than a subject and a verb, and yet still convey a complete thought. “The child ran” or “Mary ducked” or “Bob typed” are all examples of complete sentences. Each is a complete (though certainly not elaborate) thought. Each contains a noun that tells who or what the sentence is talking about, and each contains a verb that tells what the subject did.
There is nothing wrong with simple sentences like these, and often they are the best sort of sentence to use when you want to express quick, forceful ideas or actions. If you use nothing else in your writing, however, it will soon become tedious. It may also make you sound like you’re about six years old.
Most people write longer sentences, and this is where they can get confused about whether they have a true sentence or only a fragment. Many times there is the belief that if you just add more words, your fragment will be transformed into a complete thought. But “fragment” doesn’t mean “too short,” at least not in this case. It means “not complete.”
Theoretically, you could write a fragment so long it took up an entire paragraph—or an entire page—without ever sticking in a subject or a verb that related to it. This is one reason I’ve used such short sentences in my examples earlier. “Mary ducked” is a complete sentence. You don’t need to be wordy to be correct. Of course, it also makes the concept of subject/verb easier to see and understand, since nearly everything else has been left out of these sentences.
Let’s finish up with a few longer examples. “As she came out the back door, Mary ducked under the washing hanging up on the clothesline to dry in the bright sun and hot desert wind.” Obviously, this paints a clearer picture of the situation than the simple sentence, “Mary ducked.” But it is not any more complete, grammatically speaking. Notice that the sentence, stripped of its descriptive verbiage, is still about Mary and what she did (duck).
“After coming home from school, ran out in the back yard and began digging frantically in the sandbox.” After reading this, you ought to get a sense that something’s missing. And what is missing is the subject. Who came home, ran outside, and dug up the sandbox? Well, we don’t know. This makes the rest of the words fairly meaningless, as we have no idea who it’s talking about.
You have to have a subject for every sentence. Just having nouns isn’t enough. In the example above, “home,” “school,” “back yard,” and “sandbox” are all nouns (names of things or places), but none of them tell who or what the sentence is about.
“His fingers pounding the keyboard, Bob madly as he tried to finish his blog.” Again, something is decidedly missing. What did Bob (the subject of this sentence) do? We have no idea (although we could probably guess from the context in this instance that he was typing). In every sentence, you must have a verb that describes what the subject did.
And please note that just having a verb, or even several, will not do the trick. In the sentence above, “pounding” and “tried” are both verbs, but neither tells specifically what Bob is doing. Your verb has to tell something about the subject’s action, feeling, or even simply its existence.
Grammar can be a complicated subject, but most of us can get by just fine in our everyday lives with only a few simple grammar rules. You don’t always have to write in complete sentences, but it’s helpful to know when you are and when you aren’t so you don’t end up with fragments by mistake. Using complete sentences will make your writing more easily understandable by your readers, and since communication is the point of writing, that’s a good thing.