Proofreading for Common Errors
Grammar and punctuation errors can easily slip by as you write and revise your work. By following these five guidelines, you’ll learn to detect and correct the most common of these problems.
1. Avoid linking two independent clauses with a comma.
An independent clause is a group of words containing a subject and verb and expressing a complete thought. A comma splice occurs when two independent clauses are linked with just a comma:
I came to know Holmes quite well, he soon became one of my most trusted friends.
A silk hat was left at the crime scene, however, the milliner’s name was ripped from the inside.
Catching the problem: Assess every comma in your work, asking yourself whether the clauses that precede and follow it are both independent. If so, a comma alone won’t do. You have three options: 1) Replace the comma with a period. 2) Replace the comma with a semi-colon. 3) Insert a coordinating conjunction (and, but, or, nor, for, yet) before the comma. Corrections: I came to know Holmes quite well. He soon became one of my most trusted friends. -ORI came to know Holmes quite well; he soon became one of my most trusted friends. -ORI came to know Holmes quite well, and he soon became one of my most trusted friends. A silk hat was left at the crime scene; however, the milliner’s name was ripped from the inside.
2. Use a comma after an introductory phrase or clause.
An introductory phrase or clause provides “set up” for the main part of a sentence. Note the absence of necessary commas in these sentences:
According to the detective the killer must be the Hungarian diplomat.
When the ruffians heard the constable in the alley they leapt back into their hideouts.
Catching the problem:
Could the opening words be eliminated and the remaining clause would still be a grammatically sound sentence? (“The killer must be the Hungarian diplomat” and “They leapt back into their hideouts” are both grammatically sound sentences.) If so, use a comma.
Corrections:
According to the detective, the killer must be the Hungarian diplomat.
When the ruffians heard the constable in the alley, they leapt back into their hideouts.
3. Be sure your subjects and verbs agree.
Subjects and verbs should match in number: singular subjects take singular verbs, and plural subjects take plural verbs. Note the lack of agreement in each of these sentences:
Each of the fingerprints are being used to identify the suspect.
The suspect, along with his four cronies who aided in the crime, are on the run.
Catching the problem:
Identify the main noun/pronoun of the sentence. Don't be tricked by the other nouns/pronouns in the sentence, including nouns in prepositional phrases (e.g. “of the fingerprints”) or modifying phrases (e.g. “along with his four cronies”). Once you have identified the main noun of the sentence, it won’t be difficult to select the correct verb.
Corrections:
Each of the fingerprints is being used to identify the suspect.
The suspect, along with his four cronies who aided in the crime, is on the run.
4. Be sure your pronouns and antecedents agree.
Be sure that the pronouns he, she, it, one, their, and they agree in number with the nouns they are replacing. Note the lack of agreement in these sentences:
If a person wants to become a detective, they must buy a magnifying glass.
Someone left their sketch of the suspect on the desk.
Catching the problem:
Don’t be tricked into writing the same way you speak. Correct this problem by locating the noun that a pronoun refers back to and confirming that both pronoun and antecedent agree in number.
Corrections:
If a person wants to become a detective, she must buy a magnifying glass.
Someone left his sketch of the suspect on the desk.
5. Avoid Ambiguous Pronouns
You've learned how to track down pronoun antecedents (the noun a pronoun refers to), but what happens when there is more than one noun that the pronoun could be referring to? Or, what if there seems to be no antecedent noun? Make sure that each of your pronouns is clearly pointing back to a specific noun. Note the problem in each of the following sentences:
The criminal genius asked his henchman to bring his mother to their underground lair.
The criminal insisted to his nemesis that he was a genius.
In the report, it says, “The crime was committed at midnight.”
The criminal mastermind got up at 7:30, ate a bagel, and drew up plans for world- domination. This was his downfall.
Catching the problem:
Scan your work for pronouns (it, this, that, his, her, their) and be sure each pronoun is clearly identified. Pronoun ambiguity is often the result of trying to make a sentence do too many things at the same time. These errors are opportunities to make your writing more detailed and lively, so don’t be afraid to revise.
Corrections:
The criminal genius asked that his mother be brought to the underground lair; his henchman left to call a taxi for her.
The criminal insisted that he was a genius, much to his nemesis' annoyance.
The report says, “The crime was committed at midnight.”
The criminal mastermind got up at 7:30, ate a bagel, and drew up plans for world- domination. This underdeveloped scheme was his downfall.
Where in The Bedford Handbook?
Section 20: Revise run-on sentences Section 32b: Use a comma after an introductory clause or phrase Section 21: Make subjects and verbs agree Section 22: Make pronouns and antecedents agree Section 23a: Avoid Ambiguous or remote pronoun reference Also, please see the Writing Center handouts “Run-ons,” “Sentence Fragments,” “Subject-verb agreement,” and “Pronoun-Antecedent Agreement.”