Offer input on the correctness of the work. Artwork and other creative pieces might not qualify for correctness examinations, but written works usually do. Proofread the piece for spelling errors, grammatical mistakes, run-on sentences, sentence fragments, punctuation errors, vocabulary concerns or formatting issues. You don't have to list each mistake, but make sure your explanations are clear. For example, you might say, "The author often forgets necessary commas, making it difficult to understand items in a series," or "The writer has a large number of run-on sentences that make it difficult to understand where one point ends and another begins." Conclude your critique with a brief recap of your main points.
A critique of an article is the objective analysis of a literary or scientific piece, with emphasis on whether or not the author supported the main points with reasonable and applicable arguments based on facts. It's easy to get caught up in simply summarizing the points of an article without truly analyzing and challenging it. A good critique demonstrates your impressions of the article, while providing ample evidence to back up your impressions. As the critic, take time to read carefully and thoughtfully, prepare your arguments and evidence, and write clearly and cogently.