If you have commented on a thread, you can view it later by checking on your profile page. On the page that you sign in on, the top right corner has Welcome_______, Notifacations, MY PROFILE..... Click on My Profile and a new page will come up with your info on it. Look on the left side under your Avatar picture and click on newest posted threads and it will list all the threads that you commented on. It is just above newest started threads.