They will mark some spelling, grammar and punctuation errors, but they will not do your work for you. They will make general observations and suggestions about content, organization and structure. You are responsible for carefully assessing their observations and making improvements. Soulier's home page has a link to it. Neatly written, clear, thought provoking, it lacks major cliches in topic and word choice.
Diction is clear and appropriate and sentence structure nearly flawless.
Its ideas are clear and show thought and care in the selection and placement of material. Sentences and paragraphs are competent in moving from general to specific support. It is relatively free of grammatical errors. It gets a point across on a basic level. The writing is usually clear and avoids serious errors in grammar and unrelated evidence.