LOL. When I started third year I thought questions would be encouraged. I've since learned to keep my mouth shut and only ask one or two of the hundreds of questions that go through my mind each day. Then later, when I become chummy with the interns, I pick a "down time" to ask them. I've also picked up a strategy of watchful waiting for the first few days of a rotation to find out who the approachable residents are. My fellow students usually don't know the answer and/or I never see them.
I have learned to think a lot more about my questions before asking. Totally different from 1st and 2nd year where I did not hesitate to ask questions from my professors. The difference then was that my professors were there solely to teach (during that time period at least) whereas residents/attendings have clinical responsibilities and don't want you to waste their time. Seems pretty simple when you look at it, but it actually took awhile for this to sink in, especially since I am one of those people who loves to teach.
I've also since learned that if you shut up, don't complain, work hard, that most attendings notice that and then offer to teach a little (esp on rotations such as IM, OB, and I would bet surgery as well), and welcome a few (mind you only a few) pertinent questions. But first comes patient care, so you just have to shove your wants into low priority.
Another thing I struggled with was dealing with the one on one teaching/pimping. At first I didn't appreciate it at all, but eventually (after I realized how rare teaching is) I changed my attitude. Of course, sometimes a person teaches you something you already know (some people have a 'you listen, I talk' method of teaching). Then you just listen attentively, smile and say thank you and go about your way. Never show disinterest in a resident who is taking time out of their busy schedule to teach you. Sometimes I am embarassed at the way I must have appeared (unintentionally) in the beginning of the year. God, I remember in my first rotation getting upset at an attending for pimping me and then giving me a lecture which held me an hour later than I expected to go home that day (the attending was well intentioned, but the lecture really was extremely unhelpful).