During my time in college, I’ve noticed a lot of my peers making common grammar mistakes on their papers, essays, and presentations. I have always been willing to help others edit their work, but the most startling thing that always catches my eye is the grammar they use. While the content is usually excellent, these grammar mistakes are not being noticed or corrected by any of their professors. I compiled a list of the five most common grammatical errors I’ve seen other college students make and tied explanations and examples along with them. Happy writing!

Their vs. There vs. They’re

“Their” is a possessive pronoun. Ex: Their house is the second one on the left.

“There” should be used when referencing location. Ex: He put his bicycle over there an hour ago.

“They’re” is a contraction of “they” (the noun) and “are” (the verb). Ex: They’re so excited to be expecting their first child.

Your vs. You’re

“Your” is similar to “their” because it also shows possession. Ex: Your hair looks beautiful today.

“You’re” is a contraction of “you” and “are” (similar to “they’re”). Ex: You’re not going to believe what Donald Trump said today.

Its vs. It’s

“Its” is also possessive, just without the apostrophe added onto it. Ex: Its tail was longer than any I’ve ever seen before.

“It’s,” while seeming possessive due to the apostrophe, is actually a contraction of “it” and “is.” Ex: It’s going to be very hot outside today.

Affect vs. Effect

“Affect” is used when you are talking about the act of changing, using it as a verb. Ex: That speech affected me greatly.

“Effect” is used when you are talking about the change itself, using it as a noun. Ex: That speech had a great effect on me.

Than vs. Then

“Than” is used when making comparisons. Ex: This restaurant is much better than the one we went to last week.

“Then” is used when referencing time or a chronological order. Ex: I last spoke to Lori in July, but I haven’t heard anything from her since then.