To comment or post a followup question to a Q&A post, please click within the text box just beneath the post that reads, "Compose a new followup discussion."

All post contributors, as well as any others following the post, will be notified of a new followup. Only instructors and the original author can edit a particular followup, but anyone can comment on it or reply to it. 

When a new followup is posted, it will automatically be set to Unresolved, and red text reading 1 Unresolved Followup will display beneath the post in your Q&A feed, as seen below.

Individual instructors and students can resolve a followup by selecting Resolved just above the followup or Unresolved again should they have additional questions. 

If you'd like to keep track of the number of followups in a post, click on the gear icon in the top right-hand corner of your Q&A feed and select Show Followup Count.