All sentences must have a subject and predicate (can be a short as just a verb)-make sure there isn’t two verbs unless one is within a subordinate clause or a semi-colon or coordinating conjunction has been used or you will have a run-on sentence (or a comma splice if you separated them with a comma.
Run-on or comma splice sentences are sentences that should be divided into two separated sentences, joined by a coordinating conjunction (preceded by a comma), joined by a subordinating conjunction, or, if appropriate, separated by a semi-colon (e.g. Mary went to the store, John went home).
Comma splice (e.g. Mary went to the store John went home).
Run-on -> Sometimes these sentences are caused by simple carelessness-proofread carefully!
- Mary went to the store. John went home. Mary went to the store, but John went home.
- When Mary went to the store, John went home. Mary went to the store after John went home.
- Mary went to the store; John went home. (careful with semi-colons-the second sentence must either describe or elaborate on the first, or, as in this case contrast with the first-the semi-colon here is used to emphasize the contrast)
Be careful with conjunctive adverbs (however, therefore, furthermore, then, also, etc.). Conjunctive adverbs must always be separated from the rest of the sentence by commas (or a comma if the conjunctive adverb begins the sentence). Mary, however, went to the store.
- However, Mary, went to the store.
- Mary went to the store; however, John went home.
NOTE: Conjunctive adverbs CANNOT join two sentences (two independent clauses)
Coordinating conjunctions are the only words that can join two independent clauses: for, and, nor, but, or, yet, so. A useful acronym that functions as a mnemonic device is F A N B O Y S
Coordinating conjunctions are almost always preceded by a comma when they join two independent clauses (the only exception is when the two independent clauses are very short-e.g. I washed dishes and John watched television).
Beware of awkward sentence construction caused by dangling modifiers (e.g. Looking at the window, the light came on).
Note that some sentences could be grammatically correct and even true, but still be wrong:
For example: Lacking a title page and References page, as well as having no introduction or conclusion, Jeff failed the essay. (Jeff may lack these things, but presumably the writer meant that the essay lacked them-Lacking… , the essay did not receive a passing grade from Jeff.
Subject/verb agreement (must agree in person & number – e.g I am ill; she was reading; they are in class).
Noun/pronoun agreement (must agree in number and antecedent must be clear):
- When a student does not go to class, they usually fail. When students do not go to class they usually fail.
- She told her more than him. (?)
- Mary told Ellen more than Janet. (?)
Be careful with placement of adverbs-usually, they modify the word following them although they often follow the verb that they modify (e.g. The boy ran quickly) – some adverbs are often misplaced (hopefully, only, mainly, etc). For example ->
- The boy ran to the store.
- Only the boy ran to the store.
- The only boy ran to the store.
- The boy only ran to the store.
The boy ran only to the store. (2 possible meanings here because “to the store” is a prepositional phrase – “only” can modify “to” so he didn’t run from the store, or the entire phrase, so he didn’t run to any other place)
The boy ran to the only store (e.g. He only went to the party for the food).
- Do not use contractions
- Do not use slang/colloquial expressions
- Do not use “you” (your) unless you are writing directly to someone, or are writing instructions, etc.
- Be careful using “we” (us, our) unless you are allowed to write in first person and are referring to a specific group (e.g. In my class, we… ). Do not assume your reader belongs in the group of “we.”
- Generally, you are expected to use third person (Canadians are presented by American media as… They… )
- Avoid abbreviations unless they are considered standard (“e.g.” “i.e.” “St.”)
- When using acronyms, first write out the full name, followed by the acronym in parenthesis. Then you can use the acronym by itself. If the acronym is so well recognized that the full name is not needed (e.g. AIDS), you may not need to provide the full name although usually, you still should do so.
- Be careful with verb tense-make sure the tense is appropriate and that you are consistent