To improve your academic writing skills, you must ﬁrst understand possible problems with sentence structure so that you can not only recognize but write effective sentences.
To understand sentences, you must ﬁrst understand clauses, which make up sentences. A clause is deﬁned as a group of words containing both a subject and a verb.
Clauses can be independent or dependent.
There are three kinds of sentences:
Dependent clauses can function in the sentence as nouns, adjectives or adverbs:
NOTE: Use commas around the adjective clause to indicate that the information there is not essential to the sentence, i.e., not needed to identify the subject (see Improving Your Punctuation).
Absence of commas, on the other hand, indicates the information is essential to the sentence.
The bull that is in the pasture belongs to Joe. (suggests that, of all the other bulls on the farm, the one in the pasture is being identiﬁed as belonging to Joe)
The bull, which is in the pasture, belongs to Joe. (suggests that there is only one bull on the farm, so the writer is giving non-essential information by mentioning that it is in the pasture)
NOTE: The word THAT is used to introduce an essential clause (without commas), whereas WHICH is used to introduce a non-essential clause (with commas). Some grammar textbooks suggest WHICH can be used for either essential or non-essential clauses.
NOTE: A pronoun (such as which, that) must always refer speciﬁcally to one noun. The word WHICH is often used incorrectly.
Your essays should be submitted on time, WHICH is one way to be a successful student.
(Vague reference because the word which in this sentence refers to neither time nor essays.)
One way for you to be successful as a student is to submit your essays on time.
A sentence fragment is not a complete sentence. It usually lacks either a subject or a verb, or both, or contains only a dependent clause.
For example, three dogs and a goat. (no verb – what did the animals do?)
Studying too hard on weekends. (no subject – who was studying?)
Because I couldn’t ﬁnd my shoes. (contains a subject and verb, but is a dependent clause)
A run-on sentence is one in which two or more independent clauses are inappropriately joined. Remember that the length of a sentence does not determine whether it is a run-on sentence: a sentence that is correctly punctuated and correctly joined can be extremely long. Two types of run-on sentences are fused sentences and sentences with comma splice errors.
To correct a fused sentence or a comma splice error, you can use either a period, semi-colon, colon, coordinating conjunction, or subordinating conjunction.
The experiment failed. It had been left unobserved for too long.
The experiment failed; it had been left unobserved for too long.
The experiment failed: it had been left unobserved for too long.
The experiment had been left unobserved for too long, SO it failed.
The experiment failed BECAUSE it had been left unobserved for too long.
NOTE: When the conjunctive adverb is within the clause rather than at the beginning, place it between commas.
He wasn’t prepared to defend a client who was guilty; he could be persuaded, however, to accept a bribe.
NOTE: Writing the previous passage as several sentences would be more effective.
A succession of short sentences, without transitions to link them to each other, results in choppy sentences.
Our results were inconsistent. The program obviously contains an error. We need to talk to Paul Davis. We will ask him to review the program.
We will ask Paul Davis to review the program because it produced inconsistent results.
Excessive subordination is not an eﬀective substitute for choppiness.
Doug thought that he was prepared but he failed the examination which meant that he had to repeat the course before he could graduate which he didn’t want to do because it would conﬂict with his summer job.
Doug thought that he was prepared, but he failed the examination. Therefore, he would have to repeat the course before he could graduate. He did not want to do that because it would conﬂict with his summer job.
Parts of a sentence which are in sequence must all follow the same grammatical or structural principle.
I like to swim, to sail, and rowing.
I like to swim, to sail, and to row.
I like swimming, sailing, and rowing.
This report is an overview of the processes involved, the problems encountered, and how they were solved.
This report is an overview of the processes involved, the problems encountered, and the solutions devised.