Common Grammar Mistakes in AP English Language and Composition and How Feedback Helps

Key Takeaways

Definitions

Rhetorical analysis: a type of writing in which students explain how an author uses choices such as diction, structure, and appeals to influence an audience.

Sentence boundary error: a mistake that happens when ideas are joined incorrectly, such as a run-on sentence or a sentence fragment.

Why grammar feels different in AP English Language and Composition

If your teen is taking AP English Language and Composition, you have probably noticed that this course asks for more than correct grammar on its own. Students are expected to read nonfiction closely, form defensible claims, and write with control in several modes, including synthesis, rhetorical analysis, and argument. That combination is one reason common AP English Language grammar mistakes show up even in strong students.

In a regular writing class, a student may have more time to draft, revise, and edit. In AP English Language, students often write under timed conditions. They may be juggling evidence, commentary, and rhetorical purpose all at once. When that happens, grammar errors are often less about not knowing rules and more about cognitive overload. A teen may know how to avoid a comma splice during homework revision, but still write one in a 40-minute argument essay.

Teachers in this course also tend to focus on how grammar affects meaning. A sentence that is technically awkward but understandable may not matter as much as a sentence that blurs the claim, weakens the writer’s credibility, or makes analysis hard to follow. This is an important distinction for parents. In AP English Language, grammar is not just about correctness. It supports precision, tone, and the ability to communicate a line of reasoning clearly.

That is why feedback is so valuable. When a teacher or tutor points out not just that a sentence is wrong, but why it weakens the argument, students are more likely to improve. This kind of course-specific guidance reflects how writing is usually taught in rigorous high school English classrooms. Students grow faster when they can connect grammar choices to the actual demands of the assignment.

Common AP English Language grammar mistakes teachers often see

Some patterns come up again and again in AP English Language and Composition. Knowing what they look like can help you understand your teen’s teacher comments and support more productive revision at home.

Run-ons and comma splices. These are especially common in rhetorical analysis and argument essays because students are trying to connect multiple ideas quickly. A student might write, “The author repeats the phrase throughout the speech, it creates urgency for the audience.” Both ideas belong together, but they need stronger punctuation or a clearer structure.

Sentence fragments. Fragments often appear when students try to create emphasis. For example, “Because the writer wants the audience to feel responsible.” In conversation, that may sound complete. In formal analysis, it leaves the reader waiting for the main clause.

Shifts in tense. AP English Language writing often discusses texts in literary present, but students may slide between past and present without noticing. A paragraph might begin with “The speaker argues” and then move to “she appealed” and “the audience responds.” Inconsistent tense can make analysis sound less controlled.

Pronoun reference problems. In essays with multiple authors, speakers, or groups, words like “it,” “they,” and “this” can become vague. A teacher may write “unclear antecedent” in the margin when the reader cannot tell what the pronoun refers to.

Misplaced modifiers. These errors can accidentally create confusing or even humorous sentences. For instance, “Reading the passage, the author’s frustration becomes obvious” suggests the frustration is doing the reading. Students usually mean that the reader notices the frustration while reading.

Overuse of passive voice or inflated wording. Many high school students think AP writing should sound formal at all costs. That can lead to sentences like “The utilization of rhetorical devices was implemented by the author.” The sentence is grammatical, but it is wordy and weak. Clearer writing would be, “The author uses rhetorical devices to persuade the audience.”

Punctuation around quotations. Students often struggle with where to place commas, periods, and citation punctuation when embedding evidence. This matters in AP English because quotation integration is part of analytical writing, not just a formatting issue.

Subject-verb agreement in long sentences. When a sentence includes appositives, prepositional phrases, or interruptions, students may lose track of the true subject. This often happens in synthesis essays when they are trying to incorporate source material smoothly.

These mistakes are common in advanced classes because the writing tasks are complex. A teen may be thinking at a high level and still need support with sentence control. That is normal, and it is exactly where targeted feedback helps most.

How feedback helps students fix patterns instead of editing randomly

Parents sometimes see a marked-up essay and assume the goal is simply to correct every error. In AP English Language, the bigger goal is pattern recognition. A useful teacher comment does more than circle a comma splice. It helps the student see, “I tend to join complete thoughts with commas when I am rushing,” or “I lose sentence control when I try to sound academic.”

This is one reason individualized feedback is so effective. A teacher may notice that one student mainly struggles with fragments in timed writes, while another writes grammatically correct sentences that are too vague to support analysis. Those are different problems, so they need different support.

Strong feedback in this course is usually specific, limited, and connected to the writing task. For example:

• “Your claim is clear, but several sentences become run-ons when you add commentary after evidence.”
• “You are using quotations well, but pronouns like ‘this’ and ‘it’ need clearer references.”
• “Your analysis is thoughtful, but tense shifts make the paragraph harder to follow.”

That kind of guidance gives students a next step. Instead of proofreading every line with equal attention, they can revise for one or two recurring issues first. This mirrors how many experienced English teachers approach writing instruction. Students rarely improve by trying to fix everything at once. They improve by focusing on a manageable set of habits and practicing them repeatedly.

If your teen feels discouraged by comments on essays, it may help to reframe feedback as instruction rather than criticism. In a rigorous course, comments are part of the teaching. They show where your child is in the learning process and what skill is ready to develop next.

High school AP English Language and Composition writing under time pressure

One challenge that makes grammar especially tricky in high school AP English Language and Composition is timing. On an in-class rhetorical analysis or a full AP-style practice set, students have to read, plan, draft, and monitor their own writing speed. Under those conditions, even capable writers can make avoidable mistakes.

You might notice that your teen’s take-home essay looks cleaner than a timed classroom essay. That difference does not necessarily mean they are being careless in class. It often means they have not yet automated certain writing habits. Automaticity matters in AP courses. A student who no longer has to stop and think about sentence boundaries has more mental space for argument quality and evidence selection.

One helpful support at home is asking your teen what kinds of errors appear most often in timed writing versus revised writing. Their answer can reveal a lot. If punctuation errors spike only under pressure, they may need short bursts of timed practice with focused editing. If the same grammar issues appear in every setting, they may need more direct instruction and guided correction.

Some students also benefit from planning structures that reduce grammar errors before they begin. For instance, creating a quick outline with claim, evidence, and commentary can prevent overly long sentences because the writer already knows where each idea belongs. Families looking for ways to support these routines may find practical help in resources on time management, especially when balancing AP coursework with other classes and activities.

What parents can listen for when your teen talks about English class

Parents do not need to reteach grammar rules to be helpful. Often, the most useful step is listening for clues about what kind of support your teen actually needs.

If your child says, “My teacher keeps saying my writing is unclear,” that may point to pronoun reference issues, weak sentence structure, or missing transitions between ideas. If they say, “I know what I want to say, but it comes out messy,” they may need sentence-combining practice or help breaking long thoughts into manageable parts. If they say, “I lose points for grammar even when my ideas are good,” they may need support understanding which mistakes truly affect the score and which are less central.

A parent question that often opens up a better conversation is this:

What kind of writing is hardest for your teen right now?

Rhetorical analysis, synthesis, and argument each create different grammar pressures. In synthesis, students often struggle when weaving source material into their own sentences. In rhetorical analysis, they may write repetitive sentence frames such as “The author uses ethos to persuade” without expanding into precise commentary. In argument, they may produce long, tangled sentences because they are trying to qualify their claim carefully.

When parents understand the assignment type, teacher comments make more sense. This also helps families decide whether a teen needs independent practice, teacher office hours, or one-on-one academic support to work through a persistent pattern.

Guided practice that actually improves AP English grammar

Grammar improvement in this course usually works best when it stays connected to real AP writing. Worksheets on isolated comma rules can help a little, but students make stronger gains when they revise their own sentences from actual essays.

Here are a few course-aware ways guided practice can help:

• Error sorting. A student reviews teacher-marked sentences and sorts them into categories such as fragment, run-on, vague pronoun, or awkward quotation integration.
• Sentence revision practice. Instead of correcting only one final draft, the student rewrites three to five weak sentences from a rhetorical analysis and explains why the revision is stronger.
• Timed paragraph drills. The student writes one body paragraph in ten to twelve minutes, then checks only for a targeted pattern such as sentence boundaries or tense consistency.
• Model comparison. The student compares their own paragraph to a strong sample and notices how the sample handles evidence, punctuation, and commentary smoothly.

This kind of work is especially effective with a teacher, tutor, or other knowledgeable adult who can explain the reason behind the correction. That matters because many teens can fix a sentence once they are shown the answer, but they need guided instruction to apply the same skill independently the next time.

Individualized support can also reduce frustration for students who are advanced thinkers but inconsistent editors. In one-on-one settings, a tutor can slow down the writing process, identify which grammar habits appear most often, and help the student build a realistic editing checklist. Over time, that can lead to greater independence, not dependence.

Tutoring Support

If your teen is working hard in AP English Language and Composition but keeps running into the same grammar problems, extra support can be a practical next step. K12 Tutoring works with students in ways that match the course itself, including timed writing practice, revision of rhetorical analysis and argument essays, and targeted feedback on recurring sentence-level errors. The goal is not perfect writing overnight. It is clearer thinking, stronger revision habits, and more confidence in a demanding class.

For many families, tutoring is most helpful when it is used as steady academic support rather than a last-minute fix. Personalized instruction can help students understand teacher feedback, practice specific writing skills, and build the control they need for both classroom essays and AP exam preparation.

Related Resources

• How To Build Your Child’s Confidence: A Parent’s Guide – Crimson Rise
• How High-Quality, Small-Group Tutoring Can Accelerate Learning – IES (U.S. Department of Education)
• Roles in Gifted Education: A Parent’s Guide – davidsongifted.org

Trust & Transparency Statement

Last reviewed: May 2026

This article was prepared by the K12 Tutoring education team, dedicated to helping students succeed with personalized learning support and expert guidance. K12 Tutoring content is reviewed periodically by education specialists to reflect current best practices and family feedback. Have ideas or success stories to share? Email us at [email protected].