Hello there everyone!  Welcome back to school, and if you are a freshman, welcome to the best years of your life! 
  College can be an exciting and interesting time.  Soon though, it will be just a memory.  A good “memory” verb in English is “to remember”. We can use this word to explain that we have the memory of something in the past. For example, “I remember moving into my freshman dorm”. Even though I am talking about a past event, I use the present tense “remember” because my mind is thinking about the memory right now.  In the same way, if I can’t remember something, I use the verb “forget” in the present. For example, imagine I see a man but I don’t remember his name.  I can say “Oh, I’m sorry, I forget your name.  What is it?”  Notice again, that the verb is in the present because I am talking about memory right now at the moment of speaking. 
  What if I want to talk about my memory, but in the past?  For example, my roommate asked me to go to the store and buy him some orange juice in the morning.  So, after my classes, I went to the store and bought it.  Then, when I went home, I gave him the orange juice.  He said “Oh David!  You were so busy today, but you remembered to buy me the orange juice!”  I remembered about the orange juice before talking to my roommate.  But now imagine that I didn’t go to the store.  My roommate says “David, where is my orange juice?”  Then, I say to my roommate
  “Oh, I’m sorry.  I was so busy today.  I forgot to buy your orange juice”.  Notice that I use the past tense again, because I forgot before the moment of speaking.  I can’t change it now. 
So now you can talk about remembering and forgetting things both in the present and past.  If you have more questions, try this website, which has some good information about memory expressions in English. http://www.englishmedialab.com/Quizzes/advanced/memory%20related%20expressions.htm