To comment means to express an opinion or observation about something. When your teacher asks you to comment on a story you've read, she wants to hear your thoughts about it. You might comment that the main character was brave, or that the ending surprised you.

A comment can also be a noun: the actual remark or observation someone makes. If you write a comment in the margins of your essay draft, you're adding a note to yourself about something you want to improve. When someone posts a photo online, friends might leave comments saying what they think about it.

Comments can be brief reactions (“Great job!”) or longer, more detailed thoughts. In a classroom discussion, students take turns offering comments on the topic. During a presentation, audience members might save their comments until the end.