Run-on Sentences

A run-on is a grammar mistake in which two or more independent clauses are put together in the same sentence without using appropriate punctuation or a connecting word.

Sunil bought a car last week Jamal bought one, too.

Run-ons can be corrected by using connecting words, such as coordinating conjunctions and subordinating conjunctions, as well as by using appropriate punctuation.

Connecting Words: Coordinating Conjunctions

Coordinating conjunctions are and, but, or, nor, for, so, yet.

Use this pattern:

indpendent clause / comma [,] / coordinating conjunction / independent clause

Use and to indicate the addition of the second independent clause.

Sunil bought a car last week, and Linda bought one, too.
Ambassador Ciano doesn't speak Portuguese, and neither does the FSO.

Use but or yet to indicate contrast between two independent clauses.

Canada is in North America, but Brazil is in South America.
The new Ambassador is young, yet she has a lot of experience.

Use or to indicate a choice or alternative between two independent clauses.

I could meet you at your office, or you could pick me up at my apartment.

Use nor to join two negative independent clauses.

Juan will not take the train to Florida, nor will he fly.
Note: Because nor indicates "negative and," do not use a negative word in the second independent clause.

Use for to indicate that the second independent clause is the cause of the first.

Today's meeting will be short, for we all have a lot of work to do.

Use so to indicate that the second independent clause is the result of the first.

We all have a lot of work to do, so today's meeting will be short.

Connecting Words: Subordinating Conjunctions

Common subordinating conjunctions are after, although, because, before, if, once, since, though, unless, until, when, and while.

Use the following patterns:

independent clause / subordinating conjunction / independent clause
or
subordinating conjunction / independent clause / comma / independent clause

Use after, before, once, until, when and while to indicate time relationships. *

After the mechanics in the motorpool fixed the car, we never had another problem with it.
Makiko phoned me before I had a chance to reply to her email.
Once the Ambassador finishes her meeting, we can go to lunch.
We will wait at the entrance until the driver arrives.
When the President visits, everyone will sing the national anthem.
Emile can fill out the forms while Jean-Paul speaks with the FSO.

Use because and since to indicate reason.

Since Mariem is only fourteen, she can't legally drive in the United States.
Raul and Rafael were late for their appointment because the bus broke down on the way to the Embassy.

Use if to indicate cause and effect.

If we can finish our work by three o'clock, the Ambassador will let us go home early today.

Use unless to indicate negative cause and effect.

Unless we finish this paperwork today, we'll have to come in over the weekend to take care of it.

Use although and (even) though to indicate "in spite of".

Although Robert speaks seven languages fluently, he has never left the United States.
The guard decided to retire even though his supervisor asked him to stay for one more year.

Run-ons Practice 1

Insert a comma in the correct place in each combined sentence. If no comma is necessary, choose "no comma."

Swati waited an hour and a half ¤ for Robert to arrive ¤ but ¤ she finally had to admit ¤ that he wasn't going to show up. No comma ¤

Although ¤ the FSO ¤ can speak Cantonese ¤ very well ¤ he never learned to speak Mandarin. No comma ¤

3. A news crew will be filming ¤ the audience ¤ while ¤ the President is giving ¤ his speech. No comma ¤

4. Before ¤ the Ambassador makes a toast ¤ he will stand ¤ and ¤ get everyone's attention. No comma ¤

5. The driver arrived ¤ an hour late ¤ and ¤ his passengers were very ¤ upset. No comma ¤

6. The consulate ¤ is being repainted ¤ so ¤ all the windows have to be left open ¤ all afternoon. No comma ¤

7. If ¤ I can improve my French ¤ I'll be able to apply ¤ for a job ¤ as a translator. No comma ¤

8. My boss ¤ will definitely give me a raise ¤ once ¤ I show him ¤ how much money I saved the company this year. No comma ¤

9. Maria really likes her new job ¤ yet ¤ she wondered if she should have waited ¤ for ¤ a position with better benefits. No comma ¤

10. I'll meet you ¤ at six o'clock ¤ unless I ¤ run into traffic ¤ on the highway. No comma ¤