Writing run-on sentences is a common mistake among ESL students. This kind of mistake happens when two or more independent clauses (complete sentences) are joined without the appropriate punctuation or conjunction. These sentences are generally considered stylistic errors, however they are sometimes used in literature and may also be used as a rhetorical device.
A typical example of this kind of grammatical error is a comma splice. This happens when two independent clauses are joined with a comma without an accompanying coordinating conjunction. Some people do not consider a comma splice to be a run-on, however they would still not consider a comma splice to be grammatically acceptable.
The fact that a sentence is just long does not make it a run-on sentence. A sentence is a run-on only when it contains more than one independent clause and could be as short as four words. As long as clauses are punctuated correctly, it is possible to assemble multiple independent clauses in a single sentence to the extent that a properly constructed sentence can be indefinitely extended.
Decide if each sentence is correct or a run-on.
1. Give your father the keys, he needs them to open the door.
2. She loves to watch football, but she does not like to play.
3. I have never been to Bermuda, I hear it is really nice.
4. They brought lemonade and a cake with your name written on it.
5. My co-worker arrives late every morning, so he normally leaves late as well.
6. You must bring your passport any time you fly on an airplane.
7. The books in the library are old, but they are still very useful.
8. Yesterday it snowed for many hours, it stopped snowing later in the afternoon.
9. You should try the new bar downtown, it is very popular.
10. Most people I know do not vote in elections, but many people vote in every election.