Hi there! Procrastinator here!
NOTE: Feed Back is good so give it.
1) Reactive/Reaction - What was your reaction to the story? The plot, the characters? What grabbed your attention?
2) Descriptive - Describe what caused that reaction in you (specifics are nice so we know what we did right _!)
3) Prescriptive - Help us out by giving us your ideas on how we can improve our weak spots. Prescribe remedies!
4) Collaborative - Offer ideas that the writer might like to incorporate into their story. (Just remember, it is THEIR fic)