A well-written sentence, as a minimum, must fulfil the following two criteria which you should constantly check when you are proofreading and editing your own work. It must be:
- grammatically correct (language), and
- semantically correct (have clear meaning)
In order to build a sentence in English that is grammatically correct and makes sense, it is important to first understand the basic principles of sentence structures. Essentially, sentence formations can be divided into four types:
- compound-complex sentences
The secret to good writing is variation and using a mix of these types of sentences within your paragraphs in your written work.
Types of sentence structure
A simple sentence is one independent clause in a subject-verb pattern:
e.g. The Australian government introduced an official carbon tax on 1 July 2012.
A compound sentence is two independent clauses connected by a coordinating conjunction:
e.g. The Australian government introduced an official carbon tax on 1 July 2012, but this was met with opposition from the general public.
A complex sentence consists of an independent clause and a dependent clause:
e.g. As the Australian government recognised the necessity to significantly reduce greenhouse gas emissions, it introduced an official carbon tax on 1 July 2012.
A compound-complex sentence consists of more than one independent clause and one or more dependent clauses:
e.g. As the Australian government recognised the necessity to significantly reduce greenhouse gas emissions, it introduced an official carbon tax on 1 July 2012, but this was met with opposition from the general public.
(You should attempt to use a combination of the above sentence structures in your writing).
Common errors that are frequently found in students’ work are:
- sentence fragments
- run-on sentences
- lack of meaning
see below for more details:
Common error (1) - Sentence fragments
A sentence fragment is missing some of its parts. There are three main reasons why a sentence may be incomplete.
[Bad] Becoming extinct because of rising sea temperatures.
[Good] Phytoplankton could become extinct because of rising sea temperatures.
[Bad] Significantly, one particular form of Western Australian finch.
[Good] Significantly, one particular form of Western Australian finch has decreased in numbers.
[Bad] In a recent article about loss of habitat due to climate change.
[Good] In a recent article about loss of habitat due to climate change, Australian animals were shown to be particularly vulnerable.
Sentences beginning with words like so, as, because, who, which, that, are often incomplete.
Common error (2) - Run-on sentences
A run-on sentence occurs when two simple sentences are incorrectly joined:
Poverty, famine and major public health problems around the developing world are important indicators of a changing climate these issues are not being addressed globally.
There are two ways to resolve a run-on sentence:
1. Use a joining or linking word such as and, but, or, nor, for, so, yet.
Poverty, famine and major public health problems around the developing world are an important indicator of a changing climate, but these issues are not being addressed globally.
2. Make two separate sentences.
Poverty, famine and major public health problems around the developing world are an important indicator of a changing climate. These issues are not being addressed globally.
Common error (3) - Lack of Meaning
Ensure that each sentence you write has clear meaning in English. It must be fully understandable when read. If you are not sure if your sentence has clear meaning in English, perhaps think about re-writing it in a simpler and clearer way that you can fully understand (as will hopefully your reader).
Appropriate sentence length
You need to vary the length of sentences in your paragraphs. This is important to add interest to your writing, assist readability and to show relationships between ideas. Notice in the following example that all sentences are similar in length and structure. The ideas are not linked, making the writing disjointed and somewhat boring to read.
Weak example: Nursing education (Lees & Moore 2013) states that measures should be in place to avoid infection. Also, that infection rates tend to soar when hygiene standards decrease. Appropriate steps should be taken to decrease these risks. It is suggested that medical staff are educated to understand these risks.
Better example: Nursing educators (Lees & Moore 2013, Brown & Marvin 2012) argue that strict measures should be implemented to avoid infection in medical institutions. There is also much evidence to demonstrate that infection rates rise dramatically when hygiene standards begin to fall. Therefore, it is argued that appropriate steps need to be in place to decrease, and minimise, these potential risks. Furthermore, aggressive steps should be taken to ensure that all staff maintain effective hygiene and infection control.
Adapted from: RMIT University 2012, Learning Lab (opens external site) viewed 19 September 2012.