Coursework Writing Logo

Why Grammar Errors Punch Above Their Weight

You have read the sources, built a clear argument, and written a conclusion that actually answers the question. Then a stray apostrophe or a comma splice pulls your marker out of the argument and into proofreading mode. That is the frustrating thing about grammar: mistakes rarely lose marks because the examiner cannot understand you. They lose marks because they interrupt the flow of your ideas. A sentence that wobbles grammatically makes a reader pause, reread, and start to doubt the precision of everything else on the page.

The good news is that the errors which cost UK students the most marks come from a surprisingly small set of patterns. Learn to spot them and you can fix them in minutes rather than hours.

Subject-Verb Agreement: Find the Real Subject

The rule itself is simple: a singular subject takes a singular verb, a plural subject takes a plural verb. The difficulty is that academic sentences rarely keep the subject next to the verb. Words crowd in between, and it is easy to match the verb to the nearest noun instead of the actual subject.

• Long subjects. "The results of the survey suggest a link" — not suggests, because the subject is results, not survey. Cover the phrase in the middle and the sentence tells you what to do.
• Interrupting phrases. "The lecturer, along with two tutors, was present." Phrases beginning with along with, as well as and together with do not change the number of the subject.
• Collective nouns. In British English, words such as team, government and committee can take either a singular or a plural verb. Use the singular when you mean the group as a single unit, and the plural when you mean its individual members. What matters most is consistency — do not switch mid-essay.
• Indefinite pronouns. Each, every, either and neither are singular: "Each of the studies shows..." None is more flexible, but choose one form and stick with it.
• There is / There are. Look at the noun that follows. "There are three reasons why this matters."

Comma Splices and Run-On Sentences

A comma splice happens when you join two complete sentences with nothing but a comma. It is the single most common punctuation error in undergraduate essays, largely because it sounds fine when you read it aloud.

Take this: "The interviews were short, they still produced rich data." Both halves could stand alone as sentences, so a comma is not strong enough to hold them together. You have three reliable repairs: use a full stop, use a semicolon, or add a conjunction such as and, but, so or yet.

Be especially careful with however, therefore and moreover. These are adverbs, not conjunctions, so they cannot glue two sentences together. "The sample was small, however the findings were consistent" is still a splice. Write "The sample was small; however, the findings were consistent" or split it into two sentences. A run-on sentence is simply the same problem with the comma removed altogether.

Apostrophes: Three Rules That Cover Most Cases

• Possession. Singular: the student's argument. Plural ending in s: the students' arguments. Irregular plurals take 's: children's, women's.
• It's versus its. It's is short for it is or it has. Its means belonging to it. If you can swap in "it is" and the sentence still works, keep the apostrophe.
• Plurals never take apostrophes. Write the 1990s, three PhDs, the Smiths. An apostrophe here is a small but conspicuous error that markers notice instantly.

One further detail worth knowing: for joint ownership, only the second name takes the apostrophe — "Smith and Jones's study". For separate ownership, both do — "Smith's and Jones's separate studies".

Other Repeat Offenders Worth a Quick Check

• Tense drift. Keep your reporting verbs consistent. "The study found that participants reported..." not "reports".
• Dangling modifiers. "Having analysed the data, the conclusion was clear" suggests the conclusion analysed something. Write "Having analysed the data, I concluded..." instead.
• Affect and effect. Affect is usually the verb, effect the noun.
• Less and fewer. Use fewer for things you can count (fewer participants) and less for things you cannot (less time).

How to Proofread for Grammar Without Losing an Evening

Reading your essay straight through is the least effective way to catch these errors, because your brain corrects them as you go. Try these instead:

• Leave a gap. Even a few hours between drafting and proofreading makes errors visible that were invisible before.
• Read each sentence aloud. Your ear catches comma splices and missing words far faster than your eye.
• Check verbs separately. Go through and underline every subject and its verb, ignoring everything in between.
• Use the search function. Search for it's, however and semicolons, and check each one deliberately.
• Read backwards, sentence by sentence. This breaks the flow and forces you to judge each sentence on its own merits.

None of this is about writing timidly or avoiding ambitious sentences. It is about making sure that when your marker reaches your best idea, nothing small stands in its way.