Run-on Sentence – A Grade Destroyer to Run From


Are you a good runner? If so – good for you. Just make sure your sentences aren’t. Here’s why:

  • One run-on sentence can drive your grade down a full letter
  • This one mistake shows your professor that your grammar needs a lot of work
  • It makes you come across as a total beginner, even if you’re not

So, what is a run-on sentence, and how do you make sure you never write one? Here’s an example:

The high salary seems to be appealing, maybe after fifty I will have enough money to buy a personal jet.

Did you spot the mistake? Okay – here’s what it is: this sentence is really two sentences in one, and they are separated by the comma. But how do you spot this if you’re new to this stuff? First, remember a simple rule:

A Sentence Must Have a Subject and a Verb:

Sentence = Subject + Verb

Sometimes a sentence will also have an Object. But an Object is optional. Now, let me give you a little lesson in etymology (look it up – don’t be lazy. Okay – etymology means ‘the origin of the word’).

We said that the sentence above is really two sentences. But what is a sentence, really?

You see, the word ‘sentence’ comes from the Latin word ‘sententia,’ which means ‘thought.’ That’s right – thought.

And now please humor me and do the following exercise:

Imagine the Manhattan skyline for me. Okay – do you have the picture in your mind? The skyscrapers and everything? Come on, you’ve seen the photos. Perhaps you’ve even been there.

And here’s the next part of the exercise – now imagine a tropical beach. But here’s the catch: I want you to imagine the tropical beach while keeping the picture of Manhattan Skyline in your head. Yes – I want you to think of these two completely different places all at once.

How are we doing? You probably found it very difficult, if not impossible (it’s not really impossible, but it takes a lot of mental effort and creativity – like imagining a split screen, or something).

So, what have we learned here?

Here’s the lesson: when you write a run-on sentence, you ask your reader to think of two things at the same time. Why? Because in order to think, you need to think of something. And when you think of something, that something becomes the Subject of your thought (sounds familiar?) And when it becomes a subject of your thought, it either Is or Does something. And you already tried to keep two of these in your mind at the same time. It doesn’t work.

When you splice two separate sentences into one, you give your reader one subject after another without warning, and this creates confusion, even if only momentary. And that’s why your professor hates it when you do it. And that’s also why your grade suffers a lot.

So, what about the example sentence?

Let’s repeat it:

The high salary seems to be appealing, maybe after fifty I will have the enough money to buy a personal jet.

What are the two subjects of these sentences:

  • Subject 1:   the high salary (does what? –seems)
  • Subject 2:   I (the author) (will do what? –have money)

These subjects, as you have probably guessed by now, belong in separate sentences, separated by a period. A comma signifies a pause, but a period signifies a full stop and signals the oncoming of the new subject and verb. Get it?

And if the comma is used instead of the period, then the first subject “runs on” to the next one. That’s why they call it a ‘run-on sentence.’ Some writers even skip the comma. The same example without the comma is also a run-on sentence and is just as bad. So, let’s rewrite, using the correct punctuation:

The high salary seems to be appealing. Maybe after fifty I will have enough money to buy a personal jet.

Now that’s a whole ‘nother story, do you agree? And it’s easier to read, too. If you keep yourself alert to this insidious mistake and can catch it before it ‘runs on,’ you’ll be well on your way to a higher GPA, better classroom life, and a happier you!

Tutor Phil

Tutor Phil

Tutor Phil is an e-learning professional who helps adult learners finish their degrees by teaching them academic writing skills.

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