Sentence types

A sentence is a grammatical unit of one or more words that starts with a capital letter and ends with a full stop or its equivalent (! or ?) and expresses an independent statement. In academic writing, the sentence is the level at which you begin to make sense in your writing, and where you can make grammatical mistakes. It is very helpful when you are composing, editing and proofreading to be able to identify the following sentence types:

Grammar checkers will help you with your sentences in a very limited way. A green line may warn you to check for an incorrectly structured sentence. This is a useful signal, but it may give you incorrect information or miss the problem altogether. You will need to understand the structure of sentences and proofread to check that your sentences are correctly written.

Simple sentences

A simple sentence (also known as an independent clause) is the basic building block of all sentences. A simple sentence must have a main verb or verb group and a subject, and it must make complete sense on its own. When you check for correct sentence structure, you should always begin by identifying the simple sentence(s).

Simple sentences must have a verb.

INCORRECT: A thorough understanding of plagiarism of all students.

CORRECT: A thorough understanding of plagiarism is required of all students.

INCORRECT: The chief concern of the students being caught for plagiarism.

CORRECT: The chief concern of students is being caught for plagiarism.

Simple sentences must have a subject.

INCORRECT: After the training workshops, can understand plagiarism issues.

CORRECT: After the training workshops, students can understand plagiarism issues.

INCORRECT: Is sometimes not enough in an essay. 

CORRECT: Writing the author’s name is sometimes not enough in an essay.

Simple sentences must express a complete idea (i.e. make sense on their own).

INCORRECT: Although the students’ essays contained some references.

CORRECT: However, the students’ essays contained some references.

INCORRECT: The assumption being information freely available for everyone’s use.

CORRECT: The assumption is that information is freely available for everyone’s use.

Simple sentences can vary in length and style.
Students sometimes  plagiarise accidentally.

Plagiarism problems can be significantly improved with adequate student training.

Students can paraphrase and summarise the information of authors in their essays. 

To paraphrase and summarise correctly in your writing requires skill and practice. 

During note-taking, students should record reference details.

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Compound sentences

A compound sentence is formed by joining one simple sentence (independent clause) to another simple sentence (independent clause) using connecting words called ‘conjunctions’. There are two types of conjunctions that you can use to join simple sentences into one sentence.

a. Coordinating conjunctions
and, but, for (meaning because), or, nor, so, yet

Use a comma (,) before a coordinating conjunction when you write a compound sentence.

Turnitin checks will assist students to test their writing for plagiarism , but this text matching program is unable to read appropriate in-text references.
b. Conjunctive adverbs
also, conversely, for example, furthermore, however, indeed, in addition, instead, likewise, meanwhile, moreover, namely, nevertheless, otherwise, similarly, subsequently, then, therefore

Use a semicolon (;) before and a comma (,) after conjunctive adverbs when you are using them to form compound sentences.

The use of text matching software, such as Turnitin, is a significant advance in plagiarism avoidance; moreover, it assists students to monitor their own writing.

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Complex sentences

A complex sentence consists of an independent clause (simple sentence) and one or more dependent clauses (subordinating clauses). The dependent clause is introduced by either a subordinate conjunction (for an adverbial clause) or a relative pronoun (for an adjectival clause).
a. Some common subordinating conjunctions (adverbial clauses)
after, (al)though, as, because, before, if, once, since, unless, until, when, while
When the dependent clause goes before the independent clause, the clauses are separated by a comma. Do not use a comma if the dependent clause comes after the independent clause.

CORRECT: When you use Turnitin, a text matching report is generated(Correct use of a comma)

INCORRECT: A text matching report is generated, when you use Turnitin. (Incorrect use of a comma)

b. Relative pronouns (adjectival clauses)
who/that, whom, whose (people); that, which (animals, things)

The people who plagiarised in their assignments were failed.

Students for whom referencing is difficult can attend workshops to assist them.

Those students whose essays were correctly referenced received better marks.

Information that informs your writing must acknowledge its appropriate source.

Information, which can come from many sources, must be referenced.

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Compound-complex sentences

Additions can be made to compound and complex sentences to create compound-complex sentences. A compound-complex sentence must have an independent clause and two or more other clauses.

Referencing is an essential, non-negotiable feature of academic writing; therefore, students should use the university resources that assist them to achieve the required skills.

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Compound sentences

Complex sentences

Active/passive voice and nominalisation

Sentence problems



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