Common Grammar Mistakes

Their vs. There, Run-ons, Fragments, and More

Grammar mistakes are common because many English words sound alike or look similar even though they have different meanings. Learning to spot these errors helps students write more clearly and speak more confidently. Strong grammar also makes school assignments, emails, and essays easier for other people to understand. A good correction guide gives students quick ways to remember the right choice.

Many grammar errors can be fixed by checking the job a word does in a sentence. Some words show ownership, some are contractions, and some name places, numbers, or actions. Other mistakes happen when students choose a word by sound instead of meaning. By comparing the wrong form with the correct form and using simple memory tips, students can build habits that improve writing over time.

Key Facts

their shows ownership, there names a place, and they're = they are
your shows ownership, and you're = you are
its shows ownership, and it's = it is or it has
to is used for direction or as part of an infinitive, too means also or excessively, and two is the number 2
fewer is used with countable nouns, and less is used with things that are not counted individually
who is used for a subject, and whom is used for an object

Vocabulary

contraction: A contraction is a shortened form of two words joined together, such as you're for you are.
possessive: A possessive word shows that something belongs to someone or something.
subject: The subject is the person, place, thing, or idea doing the action in a sentence.
object: The object receives the action in a sentence or follows a preposition.
countable noun: A countable noun is something you can count one by one, such as books, apples, or students.

Common Mistakes to Avoid

Using they're to show ownership, because they're means they are and cannot show that something belongs to someone. Use their when you mean possession, as in their backpacks.
Writing it's for a possessive form, because it's is a contraction meaning it is or it has. Use its when something belongs to an animal, object, or idea, as in the dog wagged its tail.
Choosing less with countable items, because less is for amounts that are not counted one by one. Use fewer for things like pencils, chairs, or mistakes.
Using whom as the subject of a sentence, because whom is used as an object, not the doer of the action. Use who when the word is performing the action.

Practice Questions

1 Choose the correct word for each blank: 1) _____ going to finish the project after lunch. 2) The students put away _____ notebooks. 3) Please walk over _____ the window. 4) I want one cookie, not _____.
2 Correct the errors in these sentences: 1) Its raining, so the dog stayed in it's house. 2) We have less apples than we had yesterday. 3) Your the person who borrowed their calculator, right?
3 Explain why each correct choice fits the sentence: There going to the park with their coach, and they're excited. Identify the mistake and tell what job each correct word should do.