Though educators teach grammar throughout public school, many students in high school and even college still struggle to grasp fundamental grammatical concepts, including what constitutes a proper sentence. Run-on sentences, two independent clauses joined together without a conjunction or a semicolon, and comma splices, two independent clauses joined together by a comma without a conjunction, are still confusing to some college-level students. Parallelism, admittedly a more complex writing problem, occurs when students list items or groups of words that are not grammatically equivalent. For example, the sentence "The strikers had tried pleading, threats and shouting" is not grammatically parallel because "threats" is a noun, whereas "shouting" and "pleading" are gerunds. These and other common writing issues students need to overcome to succeed at writing academic papers.
Many students also struggle with spelling. This may be in part due to an increasing reliance among students on spell checkers and auto-complete functions in many word processors today. Furthermore, students often confuse many similarly spelled words, such as "effect" and "affect." The differences between homophones such as "its" and "it's," and "your" and "you're," trouble some students as well. Some students avoid using punctuation such as semicolons and colons altogether because they simply don't know how to use these punctuation marks.
Poor grades on papers often result from a lack of pre-planning and organization. Brainstorming a topic, outlining your ideas, solidifying your topic statement and finding a range of research sources are vital for achieving an "A" paper. Producing an organized essay or report is almost impossible without drafting your ideas first. Furthermore, organization and planning need to occur on the paragraph level as well, not just in the paper as a whole. Paragraphs that lack topic sentences will appear disjointed, as none of the ideas connect to each other through a unifying statement.
Also worth considering are logical fallacies, errors in reasoning that result in implausible or inconsistent statements. There are dozens of different logical fallacies, but some of the most common include hasty generalizations, false analogy, begging the question, self-contradiction, red herring, guilt by association and appeal to ignorance. The use of logical fallacies weakens your argument's persuasiveness and will affect the overall impression of your paper.