Subject-verb agreement errors occur most often in two situations: when a writer is in a hurry or the subject and the verb of a sentence are separated by a prepositional phrase. Subject-verb problems can undermine the integrity of writing and make it more difficult for readers to follow. A singular subject requires as singular verb whereas a plural subject requires a plural verb. For example: "Friendly customer service is our top priority." If replaced by a plural subject, the sentence would read: "Friendly customer service and reliability are our top priorities." The easiest way to avoid these mistakes is to mentally eliminate all the unnecessary words in the sentence and focus solely on the subject and verb.
Two types of pronouns exist: subject pronouns and object pronouns. Subject pronouns perform an action in the sentence while object pronouns receive the action. Like subject-verb agreement errors, writers can confuse pronouns when a lot of information is between the original subject noun and the pronoun replacing it. One of the most common pronoun errors is the misuse of "I" and "me." For example: "You and me should go to the movies." The word "me" is incorrect in this sentence as it is an object pronoun and cannot be the subject of the sentence. As "I" is a subject pronoun, the sentence should read: "You and I should go to the movies."
Run-on sentences may seem easy to spot, but just because a sentence is really long doesn't mean it's a run-on sentence. Run-on sentences are a series of clauses, or statements, strung together without proper punctuation. Grammar Girl gives the following example: "I am a woman I am a truck driver." Separating the phrase into two sentences, adding a conjunction or using a semicolon can fix this sentence. Deciding on how to fix the sentence will depend on personal style. All of these examples are correct: "I am a woman. I am a truck driver." "I am a woman, and I am a truck driver." "I am a woman; I am a truck driver."
Commas are some of most the over-used punctuations in the English language. A common but sometimes tricky way of using commas is to conjoin two main clauses in a single sentence using a conjunction and a comma. If the conjunction is missing, a comma splice has occurred. For example: "Natalie wanted to go to the theater, Max wanted to rent a movie." This error can be easily fixed by adding a conjunction after the comma: "Natalie wanted to go to the theater, but Max wanted to rent a movie."
The semicolon, similar to the comma, is another misunderstood and over-used punctuation mark. The semicolon is used to connect two related sentences without the use of conjunction. It is often used to vary style when a writer finds he has too many short sentences or too many conjunctions. However, the sentences must be related in order to use a semicolon. For example: "Susan road her bike; she wondered if the rain clouds would hold for her ride home."