How can I avoid writing run-on sentences?

This is the seventh of eight lessons about Sentence Structures. To complete this course, read each lesson carefully and then unlock and complete our materials to check your understanding.   

– Introduce the concept of sentence-structure errors

– Focus specifically on run-on sentence errors

– Provide examples to guide the learner’s understanding

Lesson 7

Now that you can hopefully recognise and use simple, compound, complex and compound-complex sentence structures in your own writing, it’s important to next turn our attention to the types of error that are common among students when writing sentences. The first major error type is called a run-on (or fused) sentence. Such run-on sentences have two or more clauses (of any type) which have been joined incorrectly – as in the following examples:

Sentence Structures 7.1 Sentence Run-Ons
Sentence Structures 7.2 Sentence Run-Ons

In example (a), the dependent clause ‘even though I don’t find it interesting’ should be joined to the following independent clause with a comma (,) to make a grammatical complex sentence. And in example (b), two independent clauses have been joined as a compound with a single comma and no coordinating conjunction, creating what’s known as a comma splice – which should be avoided at all costs.

Please note that compound-complex structures may be of almost any length and still be grammatical. Whether or not a sentence is considered to be a run-on is therefore not generally to do with its length, but with whether that sentence uses incorrect (or absent) conjunctions or punctuation. Generally, there are three ways in which a run-on sentence may seem natural even though it’s ungrammatical.

Sentence Structures 7.3 Sentence Run-On Error Types
7 of 8 Lessons Completed


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